AMENDMENT TO AGREEMENT AND PLAN OF MERGER

AMENDMENT TO AGREEMENT AND PLAN OF MERGER

AMENDMENT, dated as of May 21, 2007 (this “ Amendment ”), among Kangaroo Holdings, Inc., a Delaware corporation (“ Parent ”), Kangaroo Acquisition, Inc., a Delaware corporation and a direct wholly owned subsidiary of Parent (“ Merger Sub ”), and OSI Restaurant Partners, Inc., a Delaware corporation (the “ Company ”), to the Agreement and Plan of Merger, dated as of November 5, 2006 (the “Merger Agreement”), among Parent, Merger Sub and the Company. Unless otherwise specifically defined in this Amendment, each capitalized term used in this Amendment shall have the meaning assigned to such term in the Merger Agreement.

WHEREAS, Section 8.11 of the Merger Agreement provides that the Merger Agreement may be amended in a writing signed by the Company (acting through the Special Committee), Parent and Merger Sub;

WHEREAS, the Special Committee has determined, and the Board of Directors has determined, that it is in the best interests of the Company and its stockholders, and declared it advisable, to enter into this Amendment, and each of the Special Committee and the Board of Directors has, as of the date of this Amendment, approved and adopted this Amendment, and recommended adoption of the Merger Agreement, as amended by this Amendment, by the stockholders of the Company;

WHEREAS, the board of directors of Merger Sub has approved and adopted this Amendment;

WHEREAS, the board of directors of Parent, and Parent, as the sole stockholder of Merger Sub, in each case, have approved and adopted this Amendment; and

WHEREAS, Parent, Merger Sub and the Company desire to amend the Merger Agreement as set forth below.

NOW, THEREFORE, in consideration of the foregoing and the representations, warranties and agreements contained in this Amendment, and intending to be legally bound, Parent, Merger Sub and the Company agree as follows:

“The closing of the Merger (the “ Closing ”) shall take place at the offices of Wachtell, Lipton, Rosen & Katz, 51 West 52nd Street, New York, New York at 9:00 a.m., local time, on a date to be specified by the parties (the “ Closing Date ”) which shall be no later than the seventh business day after the satisfaction or waiver (to the extent permitted by applicable Law) of the conditions set forth in Article VI (other than those conditions that by their nature are to be satisfied at the Closing, but subject to the satisfaction or waiver of such conditions) (the “ Satisfaction Date ”), or at such other place, date and time as the Company and Parent may agree in writing.”

“On November 5, 2006, the Special Committee received the separate opinions of Wachovia Securities LLC and Piper Jaffray & Co. (the “ Advisors ”) to the effect that, as of such date, the $40 per Share in cash to be received by the holders of the Company Common Stock (other than Participating Holders) pursuant to the Merger Agreement (as in effect on November 5, 2006) was fair to such holders from a financial point of view. On May 21, 2007, the Special Committee received an opinion of Wachovia Securities LLC to the effect that, as of such date, the $41.15 per Share in cash to be received by the holders of the Company Common Stock (other than Participating Holders) pursuant to the Merger Agreement (upon giving effect this Amendment) is fair to such holders from a financial point of view. An executed copy of each such opinion has been made available to Parent. The Company has been authorized by the Advisors to permit the inclusion in full of each such opinion in the Proxy Statement (including any supplement). As of the date of this Agreement, no such opinion has been withdrawn, revoked or modified.”

“The Company shall have obtained both (i) the Company Stockholder Approval and (ii) the affirmative vote of the holders, as of the record date, of a majority of the number of shares of Company Common Stock held by holders that are not Participating Holders, voting together as a single class, to adopt the Agreement and the Merger.”