IHS INC.

Exhibit 10.17

EXECUTION COPY

IHS INC.

15 Inverness Way East

Englewood, CO 80112

October 31, 2007

Mr. Scott Key

c/o IHS Inc.

15 Inverness Way East

Englewood, CO 80112

Dear Mr. Key:

This letter, written on behalf of the Board of Directors (the “Board”) of IHS Inc., a Delaware corporation (the “Company”), confirms the terms and conditions of your employment with the Company.

1. Term of Employment. Your employment under this Letter Agreement is effective as of the date hereof (“Effective Date”) and, subject to termination as provided in Sections 7 or 8, will end on the first anniversary of the Effective Date; provided that on each anniversary of the Effective Date, the term of your employment will automatically be extended by an additional year unless the Company or you give the other party written notice, at least 30 days prior to the applicable anniversary of the Effective Date, that you do not or it does not want the term to be so extended. Such employment period, as may be so extended, will hereinafter be referred to as the “Term”.

2. Title and Duties.

(a) Position. During the Term, you will be employed by the Company as Senior Vice President, Corporate Marketing/President and COO Jane’s. You will have such duties and responsibilities and power and authority as assigned to you by the Board or the President and Chief Executive Officer of the Company (the “CEO”).

(b) Exclusive Duties. During your employment by the Company, you will devote substantially all your entire working time, attention and energies to the business of the Company and its Affiliates (as defined below) and will not, without the prior written consent of the Board undertake any other business activities. Without limiting the generality of the foregoing, you will not take any actions of the kind described in Section 11.

3. Base Salary. During the Term, the Company will pay you a minimum base salary at the annual rate of $300,000, payable in accordance with the Company’s regular payroll practices. The Compensation Committee of the Board (the “Committee”) will review your base salary annually and may, in its sole discretion, increase your base salary based on your performance and the Company’s performance. Such base salary, as may be increased, will hereinafter be referred to as your “Base Salary”.

4. Bonus. During the Term, you will be eligible to receive an annual bonus (the “Annual Bonus”) pursuant to the Company’s then current annual incentive plan. The bonus you shall be eligible to receive for fiscal year 2007 shall be in an amount equal to 50% of your Base Salary in effect at the beginning of the fiscal year at “target performance”. The performance objectives for your Annual Bonus will be determined by the CEO.

5. Annual Long-Term Incentive Grant. During the Term, you will be eligible to receive such long-term incentive grant, consisting of stock options, restricted stock, other equity-based awards, or a combination thereof, as determined by the Committee (the “Equity Grant”). The size and terms of the Equity Grant will be determined by the Committee based on your performance and the Company’s performance, as well as the terms of the equity compensation plan under which the Equity Grant is granted.

6. Other Benefits.

(a) Employee Benefits. You will be eligible to participate in the employee benefit plans, programs and arrangements maintained by the Company.

(b) Vacation. You will be entitled to not less than 24 days of paid vacation per calendar year in accordance with the Company’s vacation policy as in effect from time to time.

(c) Reimbursement. The Company will reimburse you for all reasonable expenses and disbursements in carrying out your duties and responsibilities under this Letter Agreement in accordance with Company policy for executive officers as in effect from time to time.

2

7. Termination of Employment (Non-Change in Control). Subject to Section 9 and Section 13:

(a) Resignation for Good Reason or Termination Without Cause. If you terminate your employment for Good Reason (as defined below) or you are terminated by the Company without Cause (as defined below) at any time during the Term, including by the Company giving you notice that it does not want the Term to be extended as provided in Section 1, you will receive a lump-sum cash payment equal to the sum of:

(i) any earned but unpaid Base Salary or other amounts (including reimbursable expenses and any vested amounts or benefits owing under or in accordance with the Company’s otherwise applicable employee benefit plans or programs, including retirement plans and programs) accrued or owing through the date of termination;

(ii) an amount equal to 1.5 times the sum of (x) your then Base Salary and (y) your Target Bonus for the fiscal year of such termination; and

(iii) your Target Bonus for the fiscal year of such termination, prorated for the number of days that have elapsed during such year.

In addition to the foregoing lump-sum payment:

(w) the Company will continue your participation in the Company’s medical, dental and vision plans (or if you are ineligible to continue to participate under the terms thereof, in substitute arrangements adopted by the Company providing substantially comparable benefits) for the 18-month period following the date of such termination;

(x) vesting of unvested stock options, restricted stock and other equity awards then held by you will be determined in accordance with the terms and conditions of the applicable equity compensation plan under which each such Equity Grant is granted;

(y) outplacement services during the 6-month period following such termination provided by a service provider selected by the Company for the benefit of the executive officers of the Company; and

(z) you will be credited with 2 additional years for the purposes of each of the age and service requirements of any non-qualified retirement related employee benefit plans, programs and arrangements maintained by the Company and/or its Affiliates in which you participated at the time of such termination.”

3

(b) Termination Other than for Good Reason or for Cause. If you terminate your employment other than for Good Reason (including if you give notice that you do not want to extend the Term as provided in Section 1) for if your employment is terminated by the Company for Cause, you will receive no further payments, compensation or benefits under this Letter Agreement, except you will be eligible to receive, immediately upon the effectiveness of such termination, amounts (including reimbursable expenses and any vested amounts or benefits owing under or in accordance with the Company’s otherwise applicable employee benefit plans or programs, including retirement plans and programs) accrued or owing prior to the effectiveness of your termination and such compensation or benefits that have been earned and will become payable without regard to future services.

(c) Death, Disability or Retirement. If your employment terminates by reason of death, Disability or retirement (as defined in the Company’s equity compensation plan then in effect), you or your beneficiaries will receive a lump-sum cash payment equal to the sum of:

If your employment terminates by reason of your retirement, then in addition to benefits to which you may be entitled pursuant to this Letter Agreement, your entitlements in connection with a termination of your employment pursuant to your retirement under the Company’s otherwise applicable employee benefit and retirement plans and programs (including without limitation under the Company’s equity compensation plans), will be determined in accordance with such applicable plans and programs.

For purposes of this Letter Agreement, “Good Reason” means the Company’s breach of any of its material obligations under this Letter Agreement, excluding immaterial actions (or failures of action) not taken (or omitted to be taken) in bad faith and which, if capable of being remedied, are remedied by the Company within 30 days of receipt of notice thereof given by you. For purposes of this Letter Agreement, “Cause” means any of the following: (i) conviction of or pleading guilty to a felony, (ii) commission of intentional acts of misconduct that materially impair the goodwill or business of the Company or cause material

4

damage to its property, goodwill or business, or (iii) willful refusal or willful failure to perform your material duties under this Letter Agreement after written demand that you do so. Termination of the employment shall not be deemed to be for Cause hereunder unless and until (A) written notice has been delivered to you by the Company which specifically identifies the Cause which is the basis of the termination and, if the Cause is capable of cure, you have failed to cure or remedy the act or omission so identified within 14 calendar days after written notice of such breach. For purposes of this provision, no act or failure to act on your part shall be considered “willful” unless it is done, or omitted to be done, by you in bad faith or without reasonable belief that your action or omission was in the best interest of the Company. Notwithstanding the foregoing, you shall not be deemed to have been terminated for Cause without reasonable notice to you setting forth the reasons, facts and circumstances for the Company’s intention to terminate for Cause and an opportunity for you, together with your counsel, to be heard before the Committee or the Board.

“8. Change in Control. Subject to Section 9 and Section 13:

(a) General. If there is a Change in Control (as defined below) and, within 15 months of such Change in Control, you terminate your employment for CIC Good Reason (as defined below) or you are terminated by the Company without Cause, you will receive a lump-sum cash payment equal to the sum of:

In addition to the foregoing lump-sum payment:

(w) the Company will continue your participation in the Company’s medical, dental and vision plans (or if you are ineligible to continue to participate under the terms thereof, in substitute arrangements adopted by the Company providing substantially comparable benefits), for the 24-month period following the date of such termination;

5

(x) all unvested stock options, restricted stock and other equity awards then held by you will fully vest and become exercisable as of the effective date of such termination;

For purposes of this Letter Agreement, “Change in Control” means the first to occur of:

6

Notwithstanding the foregoing, in no event will a Change in Control be considered to have occurred as a result of: (i) the distribution by the Company to its stockholder(s) of stock in an Affiliate; (ii) the contribution by the Company of some or all of its assets in a transaction governed by Section 351 of the Code; (iii) any inter-company sale or transfer of assets between the Company and any Affiliate; (iv) a dividend distribution by the Company; (v) a loan by the Company to any third party or an Affiliate; (vi) a Transaction, or series of Transactions, after which an Affiliate of the Company before such Transaction or series of Transactions, is either directly or indirectly in control of the Company thereafter; (vii) if the controlling shareholder is a trust, the acquisition, directly or indirectly, of the beneficial ownership of securities of the Company by any beneficiary of such trust if such beneficiary has a greater than 25% interest in such trust, or any descendants, spouse, estate or heirs of any such beneficiary, or a trust established for such beneficiary or for any descendants, spouse or heirs of such beneficiary; or (viii) the first underwritten primary public offering of the shares of common stock of the Company pursuant to an effective registration statement (other than a registration statement on Form S-4 or Form S-8 or any similar or successor form) under the Securities Act of 1933, as from time to time amended. For purposes of this Agreement, “Affiliate” means any individual, corporation, partnership, association, joint-stock company, trust, unincorporated association or other entity (other than the Company) that directly, or indirectly through one or more intermediaries, controls, is controlled by or is under common control with, the Company, including, without limitation, any member of an affiliated group of which the Company is a common parent corporation as provided in Section 1504 of the Internal Revenue Code of 1986, as from time to time amended (the “Code”).

For purposes of this Letter Agreement, “CIC Good Reason” means any of:

7

(b) Tax Indemnity. If it is determined that any payments and benefits that you receive from the Company or an Affiliate as a result of the Change in Control will result in you being subject to an excise tax under Section 4999 of the Code, then the Company will make a Gross-Up Payment (as defined below) to or on behalf of you as and when any such determination is made; provided you take such action (other than waiving your right to any payments or benefits) as the Company reasonably requests under the circumstances to mitigate or challenge such tax. Any such determination will be made in accordance with Sections 280G and 4999 of the Code and any other applicable law, regulations, rulings or case law. If the Company reasonably requests that you take action to avoid assessment of, or to mitigate or challenge, any such tax or assessment, including restructuring your right to receive any payments or benefits to which you are entitled (other than under this paragraph), you agree to consider such request (but in no event to waive or limit your right to any payments or benefits in a manner that would not be neutral to you from a financial point of view), and in connection with any such consideration, the Company will provide such information and advice as you may reasonably request and will pay for all reasonable expenses incurred in effecting your compliance with such request and any related taxes, fines, penalties, interest and other assessments. The term “Gross-Up Payment” means an additional amount such that you will, on an after-tax basis (including any income tax, payroll tax, further excise tax, interest, penalties and other assessments levied on any payment or benefit) receive the full amount of the payments and benefits for which the Company is liable, as if there was no excise tax under Section 4999 of the Code on any of your payments or benefits. To the extent permitted by applicable law, you agree to return to the Company the excess of any Gross-Up Payment made to you over the payment which would have been sufficient to put you in such same after-tax position. Nothing in this Section 8 is intended to violate the Sarbanes-Oxley Act and to the extent that any advance or payment obligation hereunder would do so, such obligation will be modified so as to make the advance a nonrefundable payment to you and the payment obligation null and void. This Section 8 will continue in effect until you agree that all of the Company’s obligations to you under this Section 8 have been satisfied in full or a court of competent jurisdiction makes a final determination that the Company has no further obligations to you under this Section 8, whichever comes first.

9. Release. Other than if your employment terminates by reason of death or Disability, any payment or benefit that you are eligible to receive under Sections 7 or 8 will be contingent on your execution of a release substantially in the form attached hereto as Exhibit A prior to or concurrently with the provision

8

of such payment or benefit. The payments or benefits you are eligible to receive under Sections 7 or 8 are in lieu of any termination payments or benefits which you might otherwise be eligible to receive under any standard severance policy maintained by the Company and/or its Affiliates.

10. Covenants. In exchange for the remuneration outlined above, in addition to providing service to the Company as set forth in this Letter Agreement, you agree to the following covenants:

(a) Confidentiality. You acknowledge that during your employment, you will occupy a position of trust and confidence. Accordingly, you agree that following any termination of your employment, you will keep confidential any trade secrets and confidential or proprietary information of the Company and its affiliates which are now known to you or which hereafter may become known to you as a result of your employment or association with the Company and will not at any time directly or indirectly disclose any such information to any person, firm or corporation, or use the same in any way other than in connection with the business of the Company during, and at all times after, the termination of your employment. For purposes of this Letter Agreement, “trade secrets and confidential or proprietary information” means information unique to the Company or an affiliate of the Company which has a significant business purpose and is not known or generally available from sources outside the Company or typical of industry practice, but will not include any of the foregoing (i) that becomes a matter of public record or is published in a newspaper, magazine or other periodical available to the general public, other than as a result of any act or omission of you or (ii) that is required to be disclosed by any law, regulation or order of any court or regulatory commission, department or agency; provided that you give prompt notice of such requirement to the Company to enable the Company to seek an appropriate protective order or confidential treatment.

(b) Non-Competition. You further covenant that during your employment and during the Restricted Period (as defined below), you will not, for yourself or on behalf of any other person, partnership, company or corporation, in the United States of America of elsewhere in the world, directly or indirectly, engage in, acquire any financial or beneficial interest in (except as provided in the next sentence), be employed by, or own, manage, operate or control any entity which is engaged in, any business in competition with any business of the Company or any subsidiary of the Company. Notwithstanding the preceding sentence, (i) you will not be prohibited from owning less than 1% of any publicly traded corporation, whether or not such corporation is in competition with the Company, and (ii) you will not be prohibited during the Restricted Period from being employed by or providing services to a company with multiple product-lines and/or service lines where one or more of its product-lines or service-lines is in competition with the Company so long as you have no direct or

9

indirect contact with the units(s) involved with the competitive products/services. “For purposes of this Letter Agreement, “Restricted Period” means the longer of (i) the 1-year period following termination of your employment, or (ii) in the event you receive payments pursuant to Sections 7(a), the 18-month period following termination of your employment, or (iii) in the event you receive payments pursuant to Section 8(a), the 2-year period following termination of your employment.

(c) Non-Solicitation of Employees. You further covenant that during your employment and during the Restricted Period, you will not, directly or indirectly, hire, or cause to be hired by an employer with whom you may ultimately become associated, any employee of the Company or a subsidiary of the Company at the time of termination of your employment with the Company.

(d) Employee Invention Agreement. If you have not previously executed the Company’s standard form of Employee Invention Agreement, simultaneously with the execution of this Agreement you will also execute and deliver to the Company the Company’s standard form of Employee Invention Agreement.

(e) Equitable Relief and Other Remedies. You acknowledge and agree that the Company’s remedies at law for a breach or threatened breach of any of the provisions of this Section 0 would be inadequate and, in recognition of this fact, you agree that, in the event of such a breach or threatened breach, in addition to any remedies at law, the Company, without posting any bond, will be entitled to obtain equitable relief in the form of specific performance, temporary restraining order, a temporary or permanent injunction or any other equitable remedy which may then be available.

(f) Reformation. If it is determined by a court of competent jurisdiction that any restriction in this Section 10 is excessive in duration or scope or is unreasonable or unenforceable under the law of that jurisdiction, it is the intention of the parties that such restriction may be modified or amended by the court to render it enforceable to the maximum extent permitted by the law of that jurisdiction.

(g) Survival of Provisions. Without effect as to the survival of other provisions of this Letter Agreement intended to survive the termination or expiration of your employment, the obligations contained in this Section 10 will survive the termination or expiration of your employment with the Company and will be fully enforceable thereafter.

11. Indemnification. The Company will indemnify and make permitted advances to you to the fullest extent permitted by applicable law, if you are made or threatened to be made a party to a proceeding by reason of your being

10

or having been an officer, director or employee of the Company or any of its subsidiaries or affiliates or your having served on any other enterprise as a director, officer or employee at the request of the Company. In addition, the Company will maintain insurance, at its expense, to protect you against any such expense, liability or loss to which you would be entitled to indemnification or reimbursement under the foregoing sentence.

12. Representations. By signing this Letter Agreement where indicated below, you represent that you are not subject to any employment agreement or non-competition agreement that could subject the Company or any of its affiliates to any future liability or obligation to any third party as a result of the execution of this Letter Agreement and your employment by the Company.

13. Timing and Form of Payments under Sections 7 and 8. All payments due to you under Sections 7 or 8 above shall be made no later than two and one-half months following your separation from service unless the following provisions pertaining to specified employees applies to you. You are likely to be a specified employee (as defined in Treas. Reg. §1.409A–1(i)) as of the date of a separation from service. All payments to be made to you under Sections 7 or 8 may not be made before the date that is six months after the date of separation from service (or, if earlier than the end of the six-month period, the date of your death). For this purpose, if you are not a specified employee as of the date of a separation from service, you will not be treated as subject to this requirement even if you would have become a specified employee if you had continued to provide services through the next specified employee effective date. Similarly, if you are treated as a specified employee as of the date of a separation from service, you will be subject to this requirement even if you would not have been treated as a specified employee after the next specified employee effective date had you continued providing services through the next specified employee effective date.

14. Miscellaneous Provisions.

(a) This Letter Agreement may not be amended or terminated without the prior written consent of you and the Company.

(b) This Letter Agreement may be executed in any number of counterparts which together will constitute but one agreement.

(c) This Letter Agreement will be binding on and inure to the benefit of our respective successors and permitted assigns and, in your case, your heirs and other legal representatives. If you should die while any amount would still be payable to you hereunder had you continued to live, all such amounts, unless otherwise provided herein, will be paid in accordance with the terms of this Letter Agreement to your devisee, legatee or other designee or, if there is no such designee, to your estate. The rights and obligations described in this Letter Agreement may not be assigned by either party without the prior written consent of the other

11

party; provided, however, the Company may assign its rights and obligations described in this Letter Agreement without your consent upon the transfer of all or substantially all of the business and/or assets of the Company (whether by purchase, merger, consolidation or otherwise).

(d) Subject to Section 10, all disputes arising under or related to this Letter Agreement will be settled by arbitration under the Commercial Arbitration Rules of the American Arbitration Association then in effect, such arbitration to be held in the Denver, Colorado metropolitan area, as the sole and exclusive remedy of either party. Any judgment on the award rendered by such arbitration may be entered in any court having jurisdiction over such matters.

(e) Except where prohibited by applicable law, all amounts payable to you under this Letter Agreement will be subject to required tax withholding but will otherwise not be subject to offset.

(f) All notices under this Letter Agreement will be in writing and will be deemed effective when delivered in person, by courier service, or 5 days after deposit thereof in the U.S. mail, postage prepaid, for delivery as registered or certified mail, addressed to the respective party at the address set forth below or to such other address as may hereafter be designated by like notice. Unless otherwise notified as set forth above, notice will be sent to each party as follows:

You, to:

The address as is maintained in the Company’s records

The Company, to:

IHS Inc.

15 Inverness Way East

Englewood, CO 80112

Attention: President

(g) This Letter Agreement will be governed by and construed and entered in accordance with the laws of the State of Colorado without reference to rules relating to conflict of laws.

(h) This Letter Agreement constitutes the entire agreement of the parties hereto with respect to the subject matter hereof and supersedes all prior agreements and understandings, both written and oral (including any term sheet) between the Company (or its predecessor or affiliates) and you with respect to the subject matter hereof. This Letter Agreement also supersedes any inconsistent provisions of any plan or arrangement that

12

would otherwise be applicable to you to the extent such provisions would limit any rights granted to you hereunder or expand any restrictions imposed on you hereby.

This Letter Agreement is intended to be a binding obligation upon both the Company and yourself. If this Letter Agreement correctly reflects your understanding, please sign and return one copy to Jeffrey Sisson for the Company’s records.

The above Letter Agreement correctly reflects our understanding, and I hereby confirm my agreement to the same.

13

EXHIBIT A

FULL AND COMPLETE RELEASE

I, Scott Key, in consideration for the payment of the severance described in my Letter Agreement dated October 31, 2007, for myself and my heirs, executors, administrators and assigns, do hereby knowingly and voluntarily release and forever discharge IHS Inc. (the “Company”) and its respective predecessors, successors and affiliates and current and former directors, officers and employees from any and all claims, actions and causes of action, including, but not limited to, those relating to or arising from my employment or separation of employment with the Company, including, but not limited to, under those federal, state and local laws and those applicable laws of any other jurisdiction prohibiting employment discrimination based on age, sex, race, color, national origin, religion, disability, veteran or marital status, sexual orientation or any other protected trait or characteristic, or retaliation for engaging in any protected activity, including without limitation, the Age Discrimination in Employment Act of 1967, 29 U.S.C. § 621 et seq., as amended by the Older Workers Benefit Protection Act, P.L. 101-433, the Equal Pay Act of 1963, 9 U.S.C. § 206, et seq., Title VII of The Civil Rights Act of 1964, as amended, 42 U.S.C. § 2000e et seq., the Civil Rights Act of 1866, 42 U.S.C. § 1981, the Civil Rights Act of 1991, 42 U.S.C. § 1981a, the Americans with Disabilities Act, 42 U.S.C. § 12101, et seq., the Rehabilitation Act of 1973, 29 U.S.C. § 791 et seq., the Family and Medical Leave Act of 1993, 28 U.S.C. §§ 2601 and 2611 et seq., whether KNOWN OR UNKNOWN, fixed or contingent, which I ever had, now have, or may have, or which my heirs, executors, administrators or assigns hereafter can, will or may have from the beginning of time through the date on which I sign this Full and Complete Release (this “Release”) (collectively the “Released Claims”).

I warrant and represent that I have made no sale, assignment or other transfer, or attempted sale, assignment or other transfer, of any of the Released Claims.

I fully understand and agree that:

14

If I choose to revoke this Release, I must do so by notifying the Company in writing. This written notice of revocation must be mailed by U.S. first class mail or by U.S. certified mail within the 7 day revocation period and addressed as follows:

IHS Inc.

15 Inverness Way East

Englewood, CO 80112

Attention:    President

This Release is the complete understanding between me and the Company in respect of the subject matter of this Release and supersedes all prior agreements relating to the same subject matter. I have not relied upon any representations, promises or agreements of any kind except those set forth herein in signing this Release.

In the event that any provision of this Release should be held to be invalid or unenforceable, each and all of the other provisions of this Release will remain in full force and effect. If any provision of this Release is found to be invalid or unenforceable, such provision will be modified as necessary to permit this Release to be upheld and enforced to the maximum extent permitted by law.

This Release is to be governed and enforced under the laws of the State of Colorado (except to the extent that Colorado conflicts of law rules would call for the application of the law of another jurisdiction).

This Release inures to the benefit of the Company and its successors and assigns.

I have carefully read this Release, fully understand each of its terms and conditions, and intend to abide by this Release in every respect. As such, I knowingly and voluntarily sign this Release.

15