Dean Foods Company 22,500,000 Shares1 Common Stock, par value $0.01 per share Underwriting Agreement

Exhibit 1.1

Execution Copy

Dean Foods Company

22,500,000 Shares¹

Common Stock, par value $0.01 per share

Underwriting Agreement

May 5, 2009

MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED

J.P. MORGAN SECURITIES INC.

BARCLAYS CAPITAL INC.

WACHOVIA CAPITAL MARKETS, LLC

    As Representatives of the several Underwriters

c/o Merrill Lynch, Pierce, Fenner & Smith Incorporated

One Bryant Park New York, New York 10036

Ladies and Gentlemen:

Dean Foods Company, a corporation organized under the laws of the State of Delaware (the “Company”), proposes to issue and sell an aggregate of 22,500,000 shares (the “Firm Stock”) of the Company’s common stock, par value, $0.01 per share (the “Common Stock”) to the several underwriters named in Schedule I (the “Underwriters”) pursuant to this agreement. In addition, the Company has granted to the Underwriters an option to purchase up to an additional 3,375,000 shares (the “Optional Stock”) of Common Stock to cover overallotments, if any, as provided in Section 2 hereof. The Firm Stock and, if and to the extent such option is exercised, the Optional Stock are collectively called the “Stock”. Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”), J.P. Morgan Securities Inc. (“J.P. Morgan”), Barclays Capital Inc. and Wachovia Capital Markets, LLC have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Stock. This is to confirm the agreement concerning the purchase of the Stock from the Company by the Underwriters. Any reference herein to the Registration Statement, the Base Prospectus, any preliminary prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 which were filed under the Exchange Act on or before the Effective Date of the Registration Statement or the date of the Base Prospectus, such preliminary prospectus or the Prospectus, as the case may be; and any reference herein to the terms “amend,” “amendment” or “supplement” with respect to the Registration Statement, the Base Prospectus, any preliminary prospectus or the Prospectus shall be deemed to refer to and include the filing of any document under the Exchange Act after the Effective Date of the Registration Statement or the date of the Base Prospectus, such preliminary prospectus or the Prospectus, as the case may be, deemed to be incorporated therein by reference. Certain terms used herein are defined in Section 20 hereof.

1. Representations and Warranties. The Company represents and warrants to, and agrees with, each Underwriter as set forth below in this Section 1.

(a) The Company meets the requirements for use of Form S-3 under the Act and has prepared and filed with the Commission an “automatic shelf registration statement” (as defined in Rule 405) (File number 333-149439) on Form S-3, including a related Base Prospectus, for registration under the Act of the offering and sale of the Stock. The Registration Statement initially became effective within three years of the date hereof. No notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) has been received by the Company. No order suspending the effectiveness of the Registration Statement, the Base Prospectus, any preliminary prospectus or the Prospectus has been issued by the Commission and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering has been initiated or threatened by the Commission. Such Registration Statement, including any amendments thereto filed prior to the Applicable Time, became effective upon filing. The Company will file with the Commission the Prospectus relating to the Stock in accordance with Rule 424(b). As filed, the Prospectus shall contain all information required by the Act and the rules thereunder, and, except to the extent the Representatives shall agree in writing to a modification, shall be in all substantive respects in the form furnished to you prior to the Applicable Time or, to the extent not completed at the Applicable Time, shall contain only such specific additional information and other changes (beyond that contained in the Base Prospectus) as the Company has advised you, prior to the Applicable Time, will be included or made therein. The Registration Statement, at the Applicable Time, meets the requirements set forth in Rule 415(a)(1)(x).

(b) On each Effective Date and at the Applicable Time, the Registration Statement did and will, and each preliminary prospectus and the Prospectus when first filed in accordance with Rule 424(b) and on the Closing Date and any Subsequent Closing Date, each preliminary prospectus and the Prospectus (and any supplement thereto) will, comply in all material respects with the applicable requirements of the Act, the Exchange Act and the respective rules thereunder; on each Effective Date and at the Applicable Time, the Registration Statement did not and will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein not misleading; and on the date of any filing pursuant to Rule 424(b) and on the Closing Date and any Subsequent Closing Date, the Prospectus (together with any supplement thereto) will not include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that the Company makes no representations or warranties as to the information contained in or omitted from the Registration Statement or the Prospectus (or any supplement thereto) in reliance upon and in conformity with information furnished in writing to the Company by or on behalf the Underwriters through the Representatives specifically for inclusion in the Registration Statement or the

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Prospectus (or any supplement thereto), it being understood and agreed that the only such information furnished by or on behalf of the Underwriters consists of the information described as such in Section 8 hereof.

(c) The Disclosure Package does not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from the Disclosure Package based upon and in conformity with written information furnished to the Company by the Underwriters through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by or on behalf of the Underwriters consists of the information described as such in Section 8 hereof.

(d) The documents incorporated by reference in the Disclosure Package, the Prospectus and the Registration Statement, when they became effective or were filed with the Commission, as the case may be, conformed in all material respects to the requirements of the Act or the Exchange Act, as applicable. Any further documents so filed and incorporated by reference in the Disclosure Package, the Prospectus and the Registration Statement or any further amendment or supplement thereto, when such documents become effective or are filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Act or the Exchange Act, as applicable, and the rules and regulations of the Commission thereunder.

(e) (i) At the time of filing the Registration Statement, (ii) at the time of the most recent amendment thereto for the purposes of complying with Section 10(a)(3) of the Act (whether such amendment was by post-effective amendment, incorporated report filed pursuant to Sections 13 or 15(d) of the Exchange Act or form of prospectus), (iii) at the time the Company or any person acting on its behalf (within the meaning, for this clause only, of Rule 163(c)) made any offer relating to the Stock in reliance on the exemption in Rule 163, and (iv) at the Applicable Time (with such date being used as the determination date for purposes of this clause (iv)), the Company was or is (as the case may be) a “well-known seasoned issuer” as defined in Rule 405.

(f) (i) At the earliest time after the filing of the Registration Statement that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2)) of the Stock and (ii) as of the Applicable Time (with such date being used as the determination date for purposes of this clause (ii)), the Company was not and is not an Ineligible Issuer (as defined in Rule 405), without taking account of any determination by the Commission pursuant to Rule 405 that it is not necessary that the Company be considered an Ineligible Issuer.

(g) Each Issuer Free Writing Prospectus conformed or will conform in all material respects to the requirements of the Securities Act on the date of first use, and the Company has complied with any filing requirements applicable to such Issuer Free Writing Prospectus under the Securities Act. The Company has not made any offer relating to the Stock that would constitute an Issuer Free Writing Prospectus without the prior written consent of Merrill Lynch and J.P. Morgan. The Company has retained in

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accordance with the requirements of the Securities Act all Issuer Free Writing Prospectuses that were not required to be filed pursuant to the Securities Act. Each Issuer Free Writing Prospectus, when considered together with the Disclosure Package as of the Applicable Time, did not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(h) Each of the Company and its subsidiaries (as defined in Section 20) has been duly organized and is validly existing as a corporation (or such other form of legal entity as its name and organizational documents may indicate) in good standing under the laws of the jurisdiction in which it is chartered or organized with full corporate (or other) power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Disclosure Package and the Prospectus, and, except where it would not have a Material Adverse Effect, is duly qualified to do business as a foreign corporation (or such other form of legal entity as its name and organizational documents may indicate) and is in good standing under the laws of each jurisdiction which requires such qualification.

(i) All the outstanding shares of capital stock or other ownership interests of each subsidiary of the Company have been duly and validly authorized and issued and are fully paid and non-assessable, and, except as otherwise set forth in the Disclosure Package and the Prospectus, all outstanding shares of capital stock or other ownership interests of such subsidiaries are owned by the Company either directly or through wholly-owned subsidiaries free and clear of any perfected security interest or any other security interests, claims, liens or encumbrances, except where such security interests, claims, liens or encumbrances would not have a Material Adverse Effect.

(j) There is no franchise, contract or other document of a character required to be described in the Registration Statement or Prospectus, or to be filed as an exhibit thereto, which is not described or filed as required.

(k) This Agreement has been duly authorized, executed and delivered by the Company.

(l) The shares of the Stock to be issued and sold by the Company to the Underwriters hereunder have been duly authorized and, upon payment and delivery in accordance with this Agreement, will be validly issued, fully paid and non-assessable, will conform to the description thereof contained in the Base Prospectus, will be issued in compliance with federal and state securities laws and will be free of statutory and contractual preemptive rights, rights of first refusal and similar rights.

(m) The statements set forth in the Disclosure Package and the Prospectus under the caption “Description of Capital Stock” are accurate and fair in all material respects.

(n) Neither the Company nor any subsidiary is, or, after giving effect to the offering and sale of the Stock and the application of the proceeds thereof as described in the Disclosure Package and the Prospectus, will be an “investment company” as defined in the Investment Company Act of 1940, as amended.

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(o) No consent, approval, authorization, filing with or order of any court or governmental agency or body is required in connection with the transactions contemplated herein, except such as have been obtained under the Act and the Exchange Act and such as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Stock by the Underwriters in the manner contemplated herein and in the Disclosure Package and the Prospectus.

(p) Neither the offer, issue or sale of the Stock nor the consummation of any other of the transactions herein contemplated nor the fulfillment of the terms hereof will conflict with, result in a breach or violation of, or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to (i) the charter or by-laws or similar organizational documents of the Company or any of its subsidiaries, (ii) the terms of any material indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its or their property is subject, or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties, except, with respect to clauses (ii) and (iii) above, where such conflict, breach, violation or imposition would not, individually or in the aggregate, result in a Material Adverse Effect.

(q) No holder of securities of the Company has rights to the registration of such securities under the Registration Statement.

(r) The consolidated financial statements and schedules of the Company and its consolidated subsidiaries included or incorporated by reference in the Base Prospectus, the Prospectus and the Registration Statement present fairly, in all material respects, the consolidated financial condition, results of operations and cash flows of the Company and its consolidated subsidiaries as of the dates and for the periods indicated, comply as to form with the applicable accounting requirements of the Act and have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods involved (except as otherwise noted therein). No other financial statements are required to be included or incorporated by reference in the Registration Statement.

(s) Since the date of the most recent financial statements included or incorporated by reference in the Prospectus (exclusive of any supplement thereto), there has been no material adverse change, or any development involving a prospective material adverse change, in the condition (financial or otherwise), earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business or otherwise, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

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(t) No action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or its property is pending or, to the best knowledge of the Company, threatened that (i) could reasonably be expected to have a material adverse effect on the performance of this Agreement or the consummation of any of the transactions contemplated hereby or (ii) could reasonably be expected to have a Material Adverse Effect, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(u) Each of the Company and its subsidiaries owns or leases all such properties as are necessary to the conduct of its operations as presently conducted. The Company and each of its subsidiaries has good and marketable title to all the properties and assets reflected as owned in the financial statements referred to in paragraph 1(r) above, in each case free and clear of any security interests, mortgages, liens, encumbrances, equities, claims and other defects, except such as would not, individually or in the aggregate, result in a Material Adverse Effect, or except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto). The real property, improvements, equipment and personal property held under lease by the Company or any subsidiary are held under valid and enforceable leases, with such exceptions as would not, individually or in the aggregate, result in a Material Adverse Effect or except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(v) Neither the Company nor any of its subsidiaries is in violation or default of (i) any provision of its charter or bylaws or similar organizational documents, (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which it is a party or bound or to which its property is subject, or (iii) any statute, law, rule, regulation, judgment, order or decree of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or such subsidiary or any of its properties, as applicable, except, with respect to (ii) and (iii) above, for such violations and defaults that would not, individually or in the aggregate, result in a Material Adverse Effect.

(w) Deloitte & Touche LLP, who have certified certain financial statements of the Company and its consolidated subsidiaries and delivered their report with respect to the audited consolidated financial statements and schedules included or incorporated by reference in the Base Prospectus and the Prospectus, are independent public accountants with respect to the Company and its consolidated subsidiaries within the meaning of the Act and the applicable published rules and regulations thereunder.

(x) The statistical and market-related data included under the captions included or incorporated by reference in the Disclosure Package and the Prospectus are based on or derived from sources that the Company believes to be reliable and accurate in all material respects.

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(y) Each of the Company and its subsidiaries (i) has filed all foreign, federal, state and local tax returns that are required to be filed or has requested extensions thereof, except where the failure so to file would not have a Material Adverse Effect, and (ii) has paid all taxes required to be paid by it and any other assessment, fine or penalty levied against it, to the extent they are due and payable, except where any such tax, assessment, fine or penalty is currently being contested in good faith or would not have a Material Adverse Effect, and except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(z) There are no transfer taxes or other similar fees or charges under federal law or the laws of any state, or any political subdivision thereof, required to be paid in connection with the execution and delivery of this Agreement or the issuance by the Company or sale by the Company of the Stock.

(aa) No labor problem or dispute with the employees of the Company or any of its subsidiaries exists or is threatened or imminent, and neither the Company nor any of its subsidiaries is aware of any existing or imminent labor disturbance by the employees of any of its or any of its subsidiaries’ principal suppliers, contractors or customers, that could have a Material Adverse Effect, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(bb) The Company is insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as are prudent and customary in the businesses in which they are engaged.

(cc) No subsidiary of the Company is currently prohibited, directly or indirectly, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock or other ownership interest, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s property or assets to the Company or any other subsidiary of the Company, except as described in or contemplated by the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(dd) The Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by the appropriate federal, state or foreign regulatory authorities necessary to conduct their respective businesses, and neither the Company nor any subsidiary has received any notice of proceedings relating to the revocation or modification of any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a Material Adverse Effect, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(ee) The Company and its subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset

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accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. The Company and its subsidiaries’ internal controls over financial reporting are effective, and, except as disclosed in the Disclosure Package and the Prospectus, or in any document incorporated by reference therein, since the end of the Company’s most recent audited fiscal year, there has been (i) no material weakness in the Company’s and its subsidiaries’ internal controls over financial reporting (whether or not remediated) and (ii) no change in the Company’s and its subsidiaries’ internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, such internal controls.

(ff) The Company and its subsidiaries maintain “disclosure controls and procedures” (as such term is defined in Rule 13a-15(e) under the Exchange Act); such disclosure controls and procedures are effective at the reasonable assurance level.

(gg) There is and has been no failure on the part of the Company or any of its directors or executive officers in their capacities as such, to comply in all material respects with any applicable provision of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith (the “Sarbanes-Oxley Act”), including Section 402 related to loans and Sections 302 and 906 related to certifications.

(hh) Except as set forth in the Disclosure Package and the Prospectus (exclusive of any supplement thereto), the Company and each of its subsidiaries are (i) in compliance in all material respects with any and all applicable laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“Environmental Laws”), (ii) have received and are in compliance with all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses, and (iii) have not received notice of any actual or potential liability under any Environmental Law, except where such non-compliance with Environmental Laws, failure to receive required permits, licenses or other approvals, or liability would not, individually or in the aggregate, have a Material Adverse Effect. Except as set forth in the Disclosure Package and the Prospectus (exclusive of any supplement thereto), neither the Company nor any of its subsidiaries has been named as a “potentially responsible party” under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended.

(ii) In the ordinary course of its business, the Company periodically reviews the effect of Environmental Laws on the business, operations and properties of the Company and its subsidiaries, in the course of which it identifies and evaluates associated costs and liabilities. On the basis of such review, the Company and its subsidiaries have reasonably concluded that such associated costs and liabilities would not, singly or in the aggregate, have a Material Adverse Effect, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

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(jj) The minimum funding standard under Section 302 of the Employee Retirement Income Security Act of 1974, as amended, and the regulations and published interpretations thereunder (“ERISA”), has been satisfied by each “pension plan” (as defined in Section 3(2) of ERISA) which has been established or maintained by the Company and/or one or more of its subsidiaries, and the trust forming part of each such plan which is intended to be qualified under Section 401 of the Code is so qualified; each of the Company and its subsidiaries has fulfilled its obligations, if any, under Section 515 of ERISA; neither the Company nor any of its subsidiaries maintains or is required to contribute to a “welfare plan” (as defined in Section 3(1) of ERISA) which provides retiree or other post-employment welfare benefits or insurance coverage (other than “continuation coverage” (as defined in Section 602 of ERISA)); each pension plan and welfare plan established or maintained by the Company and/or one or more of its subsidiaries is in compliance in all material respects with the currently applicable provisions of ERISA; and neither the Company nor any of its subsidiaries has incurred or could reasonably be expected to incur any withdrawal liability under Section 4201 of ERISA, any liability under Section 4062, 4063, or 4064 of ERISA, or any other liability under Title IV of ERISA.

(kk) Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the FCPA, including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA, and the Company, its subsidiaries and, to the knowledge of the Company, its affiliates have conducted their businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

(ll) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all applicable jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

(mm) Neither the Company nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”); and the Company will not directly or indirectly use the proceeds

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of the offering, or lend, contribute or otherwise make available such proceeds, to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(nn) Except as would not, individually or in the aggregate, have a Material Adverse Effect, the Company and its subsidiaries own, possess, license or have other rights to use, on reasonable terms, all patents, patent applications, trade and service marks, trade and service mark registrations, trade names, copyrights, licenses, inventions, trade secrets, technology, know-how and other intellectual property necessary for the conduct of their respective businesses as now conducted or as proposed in the Prospectus to be conducted. Neither the Company nor any of its subsidiaries has received any notice of any claim of infringement of or conflict with any such rights of others that if determined adversely to the Company or such subsidiary, would, individually or in the aggregate, have a Material Adverse Effect.

(oo) Neither the Company nor any subsidiary has taken, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, under the Exchange Act or otherwise, stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Stock.

(pp) The Stock has been approved for listing, subject to official notice of issuance, on the New York Stock Exchange.

Any certificate signed by any officer of the Company and delivered to the Representatives or counsel for the Underwriters in connection with the offering of the Stock shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Underwriter.

2. Purchase and Sale.

(a) The Firm Stock. The Company agrees to issue and sell to the several Underwriters the Firm Stock upon the terms herein set forth. On the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Underwriters agree, severally and not jointly, to purchase from the Company the respective number of shares of Firm Stock set forth opposite their names on Schedule I. The purchase price per share of Firm Stock to be paid by the several Underwriters to the Company shall be $18.25 per share. The Company shall not be obligated to deliver any of the Firm Stock to be delivered on the Closing Date, except upon payment for all such Firm Stock to be purchased on the Closing Date as provided herein.

(b) The Closing Date. Delivery of certificates for the Firm Stock to be purchased by the Underwriters and payment therefor shall be made at the offices of Sidley Austin LLP, One South Dearborn Street, Chicago, Illinois 60603 (or such other place as may be agreed to by the Company, Merrill Lynch and J.P. Morgan) at 10:00 a.m., New York time, on the third full business day following the date of this Agreement or at such other date or place as shall be determined by agreement between Merrill Lynch and J.P. Morgan, on the one hand, and the Company, on the other hand (such date and time of delivery and payment for the Firm Stock being herein called the “Closing Date”).

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(c) The Optional Stock; the Subsequent Closing Date(s). In addition, on the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Company hereby grants an option to the several Underwriters to purchase, severally and not jointly, up to an aggregate of 3,375,000 shares of Optional Stock from the Company at the same price as the purchase price per share to be paid by the Underwriters for the Firm Stock. The option granted hereunder may be exercised at any time in whole or in part and from time to time only for the purpose of covering overallotments which may be made in connection with the offering and distribution of the Firm Stock upon notice by Merrill Lynch to the Company, which notice may be given at any time within 30 days from the date of this Agreement; provided, however, that such option may not be exercised more than twice. Such notice shall set forth (i) the aggregate number of shares of Optional Stock as to which the Underwriters are exercising the option, (ii) the names and denominations in which the certificates for the Optional Stock are to be registered and (iii) the time, date and place at which such certificates will be delivered (which time and date may be simultaneous with, but not earlier than, the Closing Date; and in such case the term “Closing Date” shall refer to the time and date of delivery of certificates for the Firm Stock and the Optional Stock). Each time and date of delivery, if subsequent to the Closing Date, is called a “Subsequent Closing Date” and shall be determined by Merrill Lynch and shall not be earlier than three nor later than five full business days after delivery of such notice of exercise. If any shares of Optional Stock are to be purchased, each Underwriter agrees, severally and not jointly, to purchase the number of shares of Optional Stock (subject to such adjustments to eliminate fractional shares as Merrill Lynch may determine) that bears the same proportion to the total number of shares of Optional Stock to be purchased as the number of shares of Firm Stock set forth on Schedule I opposite the name of such Underwriter bears to the total number of shares of Firm Stock.

3. Payment and Delivery. Payment for the Stock shall be made at the Closing Date (and, if applicable, at any Subsequent Closing Date) by wire transfer of immediately available funds to the order of the Company. It is understood that the Representatives have been authorized, for their own accounts and the accounts of the several Underwriters, to accept delivery of and receipt for, and make payment of the purchase price for, the Firm Stock and any Optional Stock the Underwriters have agreed to purchase. Merrill Lynch and J.P. Morgan, each in its individual capacity and not as the Representative of the Underwriters, may (but shall not be obligated to) make payment for any Stock to be purchased by any Underwriter whose funds shall not have been received by the Representatives by the Closing Date or any Subsequent Closing Date, as the case may be, for the account of such Underwriter, but any such payment shall not relieve such Underwriter from any of its obligations under this Agreement. Delivery of the Firm Stock and the Optional Stock shall be made through the facilities of The Depository Trust Company unless Merrill Lynch and J.P. Morgan shall otherwise instruct. Time shall be of the essence, and delivery at the time and place specified in this Agreement is a further condition to the obligations of the Underwriters.

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4. Offering by the Underwriters. It is understood that the Underwriters propose to offer the Stock for sale to the public as set forth in the Prospectus.

5. Agreements. The Company agrees with each Underwriter that:

(a) Prior to the termination of the offering of the Stock, the Company will not file any amendment of the Registration Statement or supplement (including the Prospectus or any preliminary prospectus) to the Base Prospectus unless the Company has furnished you a copy for your review prior to filing and will not file any such proposed amendment or supplement to which you reasonably object. The Company and will cause the Prospectus, properly completed, and any supplement thereto to be filed in a form approved by the Representatives with the Commission pursuant to the applicable paragraph of Rule 424(b) within the time period prescribed and will provide evidence satisfactory to the Representatives of such timely filing. The Company agrees to pay the fees required by the Commission relating to the Stock within the time required by Rule 456(b)(1) without regard to the proviso therein and otherwise in accordance with Rules 456(b) and 457(r). The Company will promptly advise each Underwriter (i) when the Prospectus, and any supplement thereto, shall have been filed (if required) with the Commission pursuant to Rule 424(b), (ii) when, prior to termination of the offering of the Stock, any amendment to the Registration Statement shall have been filed or become effective, (iii) of any request by the Commission or its staff for any amendment of the Registration Statement, or any Rule 462(b) Registration Statement, or for any supplement to the Prospectus or for any additional information, (iv) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any notice objecting to its use or the institution or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act, (v) of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2), and (vi) of the receipt by the Company of any notification with respect to the suspension of the qualification of the Stock for sale in any jurisdiction or the institution or threatening of any proceeding for such purpose. The Company will use its best efforts to prevent the issuance of any such order or the occurrence of any such suspension or objection to the use of the Registration Statement and, upon such issuance, occurrence or notice of objection, to obtain as soon as possible the withdrawal of such order or relief from such occurrence or objection, including, if necessary, by filing an amendment to the Registration Statement or a new registration statement and using its best efforts to have such amendment or new registration statement declared effective as soon as practicable.

(b) If, at any time prior to the filing of the Prospectus pursuant to Rule 424(b), any event occurs as a result of which the Disclosure Package would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein in the light of the circumstances under which they were made at such time not misleading, the Company will (i) notify promptly each Underwriter so that any use of the Disclosure Package may cease until it is amended or supplemented; (ii) amend or supplement the Disclosure Package to correct such statement or omission; and (iii) supply any amendment or supplement to you in such quantities as you may reasonably request.

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(c) If, at any time when the Prospectus relating to the Stock is required to be delivered under the Act (including in circumstances where such requirement may be satisfied pursuant to Rule 172), any event occurs as a result of which the Prospectus as then supplemented would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein in the light of the circumstances under which they were made at such time not misleading, or if it shall be necessary to amend the Registration Statement, file a new registration statement or supplement the Prospectus to comply with the Act or the Exchange Act or the respective rules thereunder, including in connection with use or delivery of the Prospectus, the Company promptly will (i) notify each Underwriter of such event, (ii) prepare and file with the Commission, subject to the second sentence of paragraph (a) of this Section 5, an amendment or supplement or new registration statement which will correct such statement or omission or effect such compliance, (iii) use its best efforts to have any amendment to the Registration Statement or new registration statement declared effective as soon as practicable in order to avoid any disruption in use of the Prospectus and (iv) supply any supplemented Prospectus to you in such quantities as you may reasonably request.

(d) As soon as practicable, the Company will make generally available to its security holders and to each Underwriter an earnings statement or statements of the Company and its subsidiaries which will satisfy the provisions of Section 11(a) of the Act and Rule 158.

(e) The Company will furnish to each Underwriter and counsel for the Underwriters, without charge, signed copies of the Registration Statement (including exhibits thereto) and, so long as delivery of a prospectus by the Underwriters or dealer may be required by the Act (including in circumstances where such requirement may be satisfied pursuant to Rule 172), as many copies of each preliminary prospectus, the Prospectus and each Issuer Free Writing Prospectus and any supplement thereto as each Underwriter may reasonably request. The Company will pay the expenses of printing or other production of all documents relating to the offering.

(f) The Company will arrange, if necessary, for the qualification of the Stock for sale under the laws of such jurisdictions as the Representatives may reasonably designate, will maintain such qualifications in effect so long as required for the distribution of the Stock and will pay any fee of the Financial Industry Regulatory Authority (“FINRA”) in connection with its review of the offering; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject it to service of process in suits, other than those arising out of the offering or sale of the Stock, in any jurisdiction where it is not now so subject.

(g) The Company agrees that, unless it has obtained or will obtain the prior written consent of Merrill Lynch and J.P. Morgan, and each Underwriter agrees with the Company that, unless it has obtained or will obtain, as the case may be, the prior written consent of the Company, it has not made and will not make any offer relating to the Stock that would constitute an Issuer Free Writing Prospectus or that would otherwise

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constitute a “free writing prospectus” (as defined in Rule 405) required to be filed by the Company with the Commission or retained by the Company under Rule 433. Any such free writing prospectus consented to by Merrill Lynch, J.P. Morgan and the Company is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company agrees that (x) it has treated and will treat, as the case may be, each Permitted Free Writing Prospectus as an Issuer Free Writing Prospectus and (y) it has complied and will comply, as the case may be, with the requirements of Rules 164 and 433 applicable to any Permitted Free Writing Prospectus, including in respect of timely filing with the Commission, legending and record keeping.

(h) For a period commencing on the date hereof and ending on the 90th day after the date of the Prospectus (the “Lock-Up Period”), the Company will not, directly or indirectly, (1) offer for sale, sell, pledge or otherwise dispose of (or enter into any transaction or device that is designed to, or could be expected to, result in the disposition by any person at any time in the future of) any shares of Common Stock or securities convertible into or exchangeable for Common Stock (other than the Stock and shares issued pursuant to employee benefit plans, qualified stock option plans or other employee compensation plans existing on the date hereof or pursuant to currently outstanding options or rights not issued under one of those plans, or sell or grant options, rights or warrants with respect to any shares of Common Stock or securities convertible into or exchangeable for Common Stock (other than the grant of options pursuant to option plans or other employee compensation plans existing on the date hereof), (2) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of such shares of Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or other securities, in cash or otherwise, (3) file or cause to be filed a registration statement, including any amendments, with respect to the registration of any shares of Common Stock or securities convertible, exercisable or exchangeable into Common Stock or any other securities of the Company (other than any registration statement on Form S-8) or (4) publicly disclose the intention to do any of the foregoing, in each case without the prior written consent of Merrill Lynch and J.P. Morgan, and to cause each officer of the Company set forth on Schedule II and each director of the Company to furnish to Merrill Lynch and J.P. Morgan, prior to the Closing Date, a letter or letters, substantially in the form of Exhibit A hereto (the “Lock-Up Agreements”).

(i) The Company will apply the net proceeds from the sale of the Stock being sold by the Company as set forth in the Disclosure Package and the Prospectus.

(j) The Company will not take, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, under the Exchange Act or otherwise, stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Stock.

6. Conditions to the Obligations of the Underwriters. The obligations of the several Underwriters to purchase and pay for the Firm Stock as provided herein on the Closing Date and, with respect to any Optional Stock, any Subsequent Closing Date, shall be subject to (1) the accuracy of the representations and warranties on the part of the Company contained

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herein as of the Execution Time and the Closing Date as though then made and, with respect to any Optional Stock, as of any Subsequent Closing Date as though then made, (2) the accuracy of the statements of the Company made in any certificates pursuant to the provisions hereof, (3) the performance by the Company of its obligations hereunder and (4) each of the following additional conditions:

(a) The Prospectus, and any supplement thereto, has been filed in the manner and within the time period required by Rule 424(b); and any other material required to be filed by the Company pursuant to Rule 433(d) under the Act, shall have been filed with the Commission within the applicable time periods prescribed for such filings by Rule 433; the Company has paid the fees required by the Commission relating to the Stock within the time required by Rule 456(b)(1) without regard to the proviso therein and otherwise in accordance with Rules 456(b) and 457(r); and no stop order suspending the effectiveness of the Registration Statement or any notice objecting to its use shall have been issued and no proceedings for that purpose shall have been instituted or threatened by the Commission.

(b) FINRA shall have raised no objection to the fairness and reasonableness of the underwriting terms and arrangements.

(c) On the Closing Date and any Subsequent Closing Date, the Company shall have requested and caused Wilmer Cutler Pickering Hale and Dorr LLP, counsel for the Company, to have furnished to the Representatives their opinion, dated as of such Closing Date or Subsequent Closing Date and addressed to the Underwriters, each in form and substance satisfactory to the Representatives, to the effect set forth in Exhibit B hereto.

(d) On the Closing Date and any Subsequent Closing Date, the Representatives shall have received from Sidley Austin LLP, counsel for the Underwriters, such opinion or opinions, dated as of such Closing Date or Subsequent Closing Date and addressed to the Underwriters, with respect to the issuance and sale of the Stock, the Registration Statement, the Disclosure Package, the Prospectus (together with any supplement thereto) and other related matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

(e) On the Closing Date and any Subsequent Closing Date, the Company shall have furnished to the Representatives a certificate of the Company, signed by the principal financial or accounting officer of the Company, dated as of such Closing Date or Subsequent Closing Date, to the effect that the signer of such certificate has carefully examined the Registration Statement, the Prospectus, the Disclosure Package and any supplements or amendments thereto, and this Agreement and that:

(i) the representations and warranties of the Company in this Agreement are true and correct on and as of such Closing Date or Subsequent Closing Date with the same effect as if made on such Closing Date or Subsequent Closing Date and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to such Closing Date or Subsequent Closing Date;

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(ii) no stop order suspending the effectiveness of the Registration Statement or any notice objecting to its use has been issued and no proceedings for that purpose or pursuant to Section 8A of the Securities Act have been instituted or, to the Company’s knowledge, threatened;

(iii) the Company has not received any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2); and

(iv) since the date of the most recent financial statements included or incorporated by reference in the Prospectus (exclusive of any supplement thereto), there has been no material adverse change in the condition (financial or otherwise), earnings, business, properties or prospects of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business or otherwise, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto).

(f) On the Closing Date and any Subsequent Closing Date, the Company shall have furnished to the Representatives the opinion or opinions of Rachel A. Gonzalez, the Company’s Deputy General Counsel (or such other in-house legal officer or officers acceptable to the Representatives), signed by the Deputy General Counsel or such counsel or counsels, dated as of such Closing Date or Subsequent Closing Date and addressed to the Underwriters, to the effect set forth in Exhibit C hereto.

(g) The Company shall have requested and caused Deloitte & Touche LLP to have furnished to the Representatives, at the Execution Time and at the Closing Date and at any Subsequent Closing Date, letters, (which may refer to letters previously delivered to the Representatives), dated respectively as of the Execution Time and as of such Closing Date or Subsequent Closing Date and addressed to the Underwriters, in form and substance satisfactory to the Representatives, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in the Base Prospectus, the Registration Statement and the Prospectus.

(h) Subsequent to the Execution Time or, if earlier, the dates as of which information is given in the Registration Statement (exclusive of any amendment thereof), the Disclosure Package (exclusive of any supplement thereto) and the Prospectus (exclusive of any supplement thereto), there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (g) of this Section 6 or (ii) any change, or any development involving a prospective change, in or affecting the condition (financial or otherwise), earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business or otherwise, except as set forth in or contemplated in the Disclosure Package and the Prospectus (exclusive of any supplement thereto) the effect of which, in

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any case referred to in clause (i) or (ii) above, is, in the sole judgment of the Representatives, so material and adverse as to make it impractical or inadvisable to proceed with the offering, sale or delivery of the Stock as contemplated by the Registration Statement (exclusive of any amendment thereof), the Disclosure Package (exclusive of any supplement thereto) and the Prospectus (exclusive of any supplement thereto).

(i) Subsequent to the Execution Time, there shall not have been any decrease in the rating of any of the Company’s debt securities by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g) under the Act) or any notice given of any intended or potential decrease in any such rating or of a possible change in any such rating that does not indicate the direction of the possible change.

(j) The New York Stock Exchange shall have approved the Stock for listing, subject only to official notice of issuance.

(k) The Lock-Up Agreements between the Underwriters, on the one hand, and the officers of the Company set forth on Schedule II and the directors of the Company, on the other hand, delivered to the Underwriters on or before the date of this Agreement, shall be in full force and effect on the Closing Date and any Subsequent Closing Date.

All opinions, letters, evidence and certificates mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

7. Reimbursement of Underwriters’ Expenses. If the sale of the Stock provided for herein is not consummated because any condition to the obligations of the Underwriters set forth in Section 6 hereof is not satisfied, because of any termination pursuant to Section 9 hereof or because of any refusal, inability or failure on the part of the Company to perform any agreement herein or comply with any provision hereof other than by reason of a default by an Underwriter, the Company will reimburse each Underwriter on demand for all out-of-pocket expenses (including reasonable fees and disbursements of counsel) that shall have been incurred by such Underwriter in connection with the proposed purchase and sale of the Stock.

8. Indemnification and Contribution. (a) The Company agrees to indemnify and hold harmless each Underwriter, the directors, officers, employees and agents of each Underwriter and each person who controls any Underwriter within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement as originally filed or in any amendment thereof, or in the Base Prospectus, any preliminary prospectus, the Prospectus, any Issuer Free Writing Prospectus or in any amendment thereof or supplement thereto, or the Company’s earnings release, dated May 1, 2009, regarding the Company’s results for the quarter ended March 31, 2009, or arise out of or are based

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upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made therein in reliance upon and in conformity with written information furnished to the Company by or on behalf of the Underwriters through the Representatives specifically for inclusion therein. This indemnity agreement will be in addition to any liability which the Company may otherwise have.

(b) Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, and its directors and officers who signs the Registration Statement, and each person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each Underwriter, but only with reference to written information relating to the Underwriters furnished to the Company by or on behalf of the Underwriters through the Representatives specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability which each Underwriter may otherwise have. The Company acknowledges that the second sentence of the first paragraph and the last paragraph under the caption “Price Stabilization and Short Positions” under the heading “Underwriting” in the Prospectus (in each case not including the Base Prospectus), constitute the only information furnished in writing by or on behalf of the Underwriters for inclusion in the Prospectus.

(c) Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section 8, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a) or (b) of this Section unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) of this Section 8. The indemnifying party shall be entitled to appoint counsel of the indemnifying party’s choice at the indemnifying party’s expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be satisfactory to the indemnified party. Notwithstanding the indemnifying party’s election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest, (ii) the actual or potential defendants in,

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or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party, (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent (1) includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding, and (2) does not include a statement as to, or an admission of, fault, culpability or a failure to act, by or on behalf of any indemnified party.

(d) In the event that any indemnity provided in paragraph (a) or (b) of this Section 8 is unavailable to or insufficient to hold harmless an indemnified party for any reason, the Company, on the one hand, and the Underwriters, on the other, agree to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively “Losses”) to which the Company and the Underwriters may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and by the Underwriters, on the other, from the offering of the Stock. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company, on the one hand, and the Underwriters, on the other, shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company, on the one hand, and of the Underwriters, on the other, in connection with the statements or omissions that resulted in such Losses, as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by them, and benefits received by the Underwriters shall be deemed to be equal to the total underwriting discounts and commissions, in each case as set forth on the cover page of the Prospectus. The Company and the Underwriters agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), (i) in no case shall any Underwriter be responsible for any amount in excess of the underwriting discount or commission applicable to the Stock purchased by such Underwriter hereunder and (ii) no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 8, each person who controls an Underwriter within the meaning of either the Act or the Exchange Act and each director, officer, employee and agent of an Underwriter shall have the same rights to contribution as such Underwriter, and each person who controls

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the Company within the meaning of either the Act or the Exchange Act, each officer of the Company who shall have signed the Registration Statement and each director of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

9. Termination. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Stock, if at any time prior to such time (i) trading in the Company’s Common Stock shall have been suspended by the Commission or the New York Stock Exchange or trading in securities generally on the New York Stock Exchange shall have been suspended or limited or the settlement of such trading generally shall have been materially disrupted or minimum prices shall have been established on such Exchange, (ii) a banking moratorium shall have been declared either by federal or New York State authorities, or (iii) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war, or other material adverse change in financial markets or calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impractical or inadvisable to proceed with the offering, sale or delivery of the Stock as contemplated by the Prospectus (exclusive of any supplement thereto).

10. Representations and Indemnities to Survive. The respective agreements, representations, warranties, indemnities and other statements of the Company or its officers and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of the Underwriters, the Company, or any of the officers, directors, employees, agents or controlling persons referred to in Section 8 hereof, and will survive delivery of and payment for the Stock. The provisions of Sections 7 and 8 hereof shall survive the termination or cancellation of this Agreement.

11. Notices. All communications hereunder will be in writing and effective only on receipt, and, if sent to Merrill Lynch, J.P. Morgan or the Representatives, will be mailed, delivered or telefaxed to Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, Attention: Syndicate Department (Fax: (646)  ###-###-####), with a copy, in the case of any notice pursuant to Section 8(c) to Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, Attention: ECM Legal (Fax: (212)  ###-###-####); or, if sent to the Company, will be mailed, delivered or telefaxed to Dean Foods Company, 2515 McKinney Avenue, Suite 1200, Dallas, Texas 75201, Attention: General Counsel (Fax: 214 ###-###-####).

12. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers, directors, employees, agents and controlling persons referred to in Section 8 hereof, and no other person will have any right or obligation hereunder.

13. Research Analyst Independence. The Company acknowledges that each Underwriter’s research analysts and research departments are required to be independent from its investment banking division and are subject to certain regulations and internal policies, and that each Underwriter’s research analysts may hold views and make statements or investment recommendations and/or publish research reports with respect to the Company and/or the

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offering that differ from the views of its investment banking division. The Company hereby waives and releases, to the fullest extent permitted by law, any claims that the Company may have against each Underwriter with respect to any conflict of interest that may arise from the fact that the views expressed by its independent research analysts and research departments may be different from or inconsistent with the views or advice communicated to the Company by each Underwriter’s investment banking division. The Company acknowledges that each Underwriter is a full service securities firm and as such from time to time, subject to applicable securities laws, may effect transactions for its own account or the account of its customers and hold long or short positions in debt or equity securities of the companies that may be the subject of the transactions contemplated by this Agreement.

14. No Fiduciary Duty. The Company hereby acknowledges that (a) the purchase and sale of the Stock pursuant to this Agreement is an arm’s-length commercial transaction between the Company, on the one hand, and each Underwriter and any affiliate through which it may be acting, on the other, (b) each Underwriter is acting as principal and not as an advisor, agent or fiduciary of the Company, (c) the Company’s engagement of each Underwriter in connection with the offering and the process leading up to the offering is as independent contractors and not in any other capacity, and (d) each Underwriter and its affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company and that each Underwriter has no obligation to disclose any of such interests by virtue of any advisory, agency or fiduciary relationship. Furthermore, the Company agrees that it is solely responsible for making its own judgments in connection with the offering (irrespective of whether any Underwriter has advised or is currently advising the Company on related or other matters). The Company agrees that it will waive any claim that it may have that any Underwriter has rendered advisory services of any nature or respect, or owes an agency, fiduciary or similar duty to the Company, in connection with such transaction or the process leading thereto.

15. Integration. This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company and the Underwriters, or any of them, with respect to the subject matter hereof.

16. Applicable Law. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

17. Waiver of Jury Trial. The Company hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

18. Counterparts. This Agreement may be signed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same agreement.

19. Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

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20. Definitions. The terms which follow, when used in this Agreement, shall have the meanings indicated.

“Act” and “Securities Act” shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

“Applicable Time” means 6:30 p.m. (New York City time) May 5, 2009.

“Base Prospectus” shall mean the base prospectus referred to in paragraph 1(a) above contained in the Registration Statement at the Applicable Time.

“Business Day” shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in New York City.

“Commission” shall mean the Securities and Exchange Commission.

“Disclosure Package” shall mean as of the Applicable Time, (i) the Base Prospectus, including any preliminary prospectus supplement, (ii) any Issuer Free Writing Prospectuses identified in Schedule III hereto, (iii) any other Free Writing Prospectus that the parties hereto shall hereafter expressly agree in writing to treat as part of the Disclosure Package and (iv) the information set forth in Schedule IV hereto.

“Effective Date” shall mean each date and time that the Registration Statement and any post-effective amendment or amendments thereto became or become effective.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

“Execution Time” shall mean the date and time that this Agreement is executed and delivered by the parties hereto.

“FCPA” means Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder.

“Free Writing Prospectus” shall mean a free writing prospectus, as defined in Rule 405.

“Issuer Free Writing Prospectus” shall mean an issuer free writing prospectus, as defined in Rule 433.

“Material Adverse Effect” shall mean a material adverse effect on the condition (financial or otherwise), earnings, business, properties or prospects of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business or otherwise.

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“preliminary prospectus” shall mean any preliminary prospectus supplement to the Base Prospectus relating to the Stock and the offering thereof and that is used prior to the filing of the Prospectus, together with the Base Prospectus.

“Prospectus” shall mean the final prospectus supplement relating to the Stock and the offering thereof that is first filed pursuant to Rule 424(b) after the Applicable Time, together with the Base Prospectus.

“Registration Statement” shall mean the registration statement referred to in paragraph 1(a) above, including exhibits and financial statements and any prospectus supplement relating to the Stock that is filed with the Commission pursuant to Rule 424(b) and deemed part of such registration statement pursuant to Rule 430B, as amended on each Effective Date and, in the event any post-effective amendment thereto becomes effective prior to the Closing Date or any Subsequent Closing Date, shall also mean such registration statement as so amended.

“Rule 158”, “Rule 163”, “Rule 164”, “Rule 172”, “Rule 401(g)(2)”, “Rule 405”, “Rule 415”, “Rule 424”, “Rule 430B”, “Rule 433”, “Rule 456”, “Rule 457” and “Rule 462 refer to such rules under the Act.

“subsidiary” shall have the meaning set forth in Rule 405.

“Well-Known Seasoned Issuer” shall mean a well-known seasoned issuer, as defined in Rule 405.

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company and the Underwriters.

The foregoing agreement is hereby confirmed and accepted by the

Representatives as of the date specified above.

MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED

J.P. MORGAN SECURITIES INC.

BARCLAYS CAPITAL INC.

WACHOVIA CAPITAL MARKETS, LLC

    Acting as Representatives of the several Underwriters named in the

    attached Schedule I

SCHEDULE I

SCHEDULE II

Officers Delivering Lock-up Agreements

Gregg L. Engles

Jack F. Callahan, Jr.

Joseph E. Scalzo

Gregg A. Tanner

Harrald F. Kroeker

Deborah B. Carosella

Kelly Duffin-Maxwell

Richard Fehr

Steven J. Kemps

Gregory A. McKelvey

Paul T. Moskowitz

Ronald McCrummen

SCHEDULE III

Schedule of Free Writing Prospectuses included in the Disclosure Package

None.

SCHEDULE IV

Other Information Included in the Disclosure Package

The price at which the shares of the Stock will be sold to the public: $18.25 per share.

The number of shares of the Firm Stock being sold to the public: 22,500,000 shares.

The number of shares of the Optional Stock being sold to the public: 3,375,000 shares.