Exhibit 10.18

Summary of 2005 Compensation for  Executive Officers and Non-Employee Directors

Executive Officer Compensation

In January 2005, the Board of Directors of PRAECIS PHARMACEUTICALS INCORPORATED (the "Company"), upon recommendation of the Compensation Committee,
approved the 2005 compensation for the Company's executive officers. The table below sets forth 2005 compensation and potential bonus award values under the Company's Executive Management Bonus Plan
(the "Bonus Plan"), as well as certain other compensation.

|Name and Title                                                                               |  | Annual
Salary(1) |         | Bonus
Target
Award
Value(2) |    | Other
Compensation
|-------------------------------------------------------------------------------------------- |  | ---------------- | ------- | --------------------------- | -- | ------------------
|Kevin F. McLaughlin
President and Chief Executive Officer                                    |  | $                | 350,000 |                             | 50 | %                 
|Edward C. English
Vice President, Chief Financial Officer, Treasurer
and Assistant Secretary |  | $                | 208,000 |                             | 25 | %                 
|Marc B. Garnick, M.D.
Executive Vice President and Chief Medical
and Regulatory Officer      |  | $                | 340,000 |                             | 40 | %                 
|Richard W. Wagner, Ph.D.
Executive Vice President, Discovery Research                        |  | $                | 267,500 |                             | 30 | %                 
|Michael J. Keavany
Senior Vice President, Sales and Marketing                                |  | $                | 270,000 |                             | 30 | %                 

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None of the Company's executive officers has an employment agreement and the executive compensation described above has been or will be (with respect to actual
bonus payments for 2005) approved by the Board of Directors, upon recommendation of the Compensation Committee, but is not otherwise set forth in a written agreement between the Company and such
executive officers.

Each
executive officer is a party to a letter agreement with the Company providing for certain benefits in the event of the executive's termination upon or within one year following a
change of control of the Company. These agreements are filed as exhibits to the Company's Annual Report on Form 10-K for the year ended December 31, 2004 and will be
described in more detail under "Employment Agreements/Change of Control Arrangements" in the Company's Proxy Statement for its 2005 Annual Meeting of Stockholders.

Each
executive officer may also be eligible for an annual option grant to purchase shares of common stock, par value $.01 per share, of the Company. Annual option grants for executive
officers generally vest and become exercisable in equal monthly installments over a three-year period from the

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date
of grant so long as the individual continues to be an employee of the Company. The amount of such annual grants, if any, will be dependent upon corporate and individual performance during 2005.

The
executive officers are also eligible to participate in the Company's employee benefit plans, which include health, dental, life and long-term disability insurance; three
weeks of vacation per year; twelve statutory/ Company designated holidays each year; and the ability to participate in the Company's 401(k) Plan and Employee Stock Purchase Plan.

Non-Employee Director Compensation

For 2005, non-employee directors will receive the following annual compensation, which has been approved by the Company's Board of Directors and
remains unchanged from 2004:

Cash Compensation



Stock Compensation

Directors are eligible to receive stock options under our Third Amended and Restated 1995 Stock Plan. Non-employee directors generally receive an
annual option grant to purchase 10,000 shares of common stock, par value $.01 per share, of the Company. Each annual option grant vests and becomes exercisable in equal monthly installments over a
one-year period from the date of grant so long as the individual continues to be a member of our Board of Directors.

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