(Credit Agreement)

Exhibit 10.34

Execution Version

FIRST AMENDMENT

(Credit Agreement)

FIRST AMENDMENT, dated as of March 28, 2006 (this “Amendment”), to the SENIOR REVOLVING CREDIT AGREEMENT, dated as of May 10, 2005 (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among LAZARD GROUP LLC, a Delaware limited liability company (the “Company”), the Banks from time to time parties thereto, CITIBANK, N.A., a national banking association (“Citibank”), and THE BANK OF NEW YORK, New York Branch (“The Bank of New York”), and JPMORGAN CHASE BANK, N.A., a New York banking corporation as a Bank (in such capacity, “JPMorgan Chase Bank”, and together with Citibank and The Bank of New York, the “Banks”) and as Administrative Agent for the Banks thereunder (in such capacity, the “Administrative Agent”).

W I T N E S S E T H :

WHEREAS, the Company, the Banks and the Administrative Agent are parties to the Credit Agreement;

WHEREAS, the Company has requested, and upon this Amendment becoming effective, the Banks have agreed, to amend certain provisions of the Credit Agreement upon the terms and conditions set forth herein.

NOW, THEREFORE, the parties hereto agree as follows:

SECTION 1. DEFINITIONS

1.1 Defined Terms. Unless otherwise defined herein, terms defined in the Credit Agreement and used herein shall have the meanings given such terms in the Credit Agreement.

SECTION 2. AMENDMENTS TO CREDIT AGREEMENT

2.1 Amendment of Section 7.2. Section 7.2 is hereby amended by (i) adding a new paragraph (s) after paragraph (r) thereof to read in its entirety as follows; (ii) by deleting the “and” appearing after clause (q) thereof and (iii) by deleting the “.” at the end of clause (r) thereof and inserting, in lieu thereof “; and”:

“(s) Indebtedness under the 4.25% senior note in the principal amount of $96,000,000 and under the 4.60% subordinated note in the principal amount of $50,000,000, both due February 28, 2008 and issued by the Company in favor of Banca Intesa S.p.A., and incurred by the Company in connection with the dissolution of the Intesa Strategic Alliance and any Permitted Refinancing Indebtedness incurred to Refinance such Indebtedness; provided that the senior note is used to repurchase the equity interest of Banca Intesa S.p.A. in Lazard & Co. S.r.l. and the subordinated note is used to refinance in full that certain 3.0% subordinated promissory note, dated June 10, 2003, in the principal amount of

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$50,000,000, issued by Lazard & Co. S.r.l. in favor of Banca Intesa S.p.A.”

SECTION 3. MISCELLANEOUS

3.1 Limited Effect. Except as expressly amended, modified and supplemented hereby, the Credit Agreement is, and shall remain, in full force and effect in accordance with its terms.

3.2 Effectiveness. This Amendment shall become effective as of the date (the “First Amendment Effective Date”) of receipt by the Administrative Agent of counterparts hereof duly executed by the Company and Lenders constituting the Required Lenders.

3.3 Representations and Warranties. On and as of the date hereof and after giving effect to this Amendment, the Company hereby confirms, reaffirms and restates the representations and warranties set forth in Section 4 of the Credit Agreement mutatis mutandis, except to the extent that such representations and warranties expressly relate to a specific earlier date in which case the Company hereby confirms, reaffirms and restates such representations and warranties as of such earlier date.

3.4 Counterparts. This Amendment may be executed by one or more of the parties hereto on any number of separate counterparts, and all of said counterparts taken together shall be deemed to constitute one and the same instrument. A set of the copies of this Amendment signed by all the parties shall be lodged with the Company and the Administrative Agent. This Amendment may be delivered by facsimile transmission of the relevant signature pages hereof.

3.5 GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

[Signature page to follow]

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed by their respective officers thereunto duly authorized as of the day and year first above written.

Signature page to First Amendment to the Credit Agreement