Stock Option Agreement - The Corporate Executive Board Co. and Michael D'Amato
                                                                               
                     The Corporate Executive Board Company
                                 The Watergate
                         600 New Hampshire Avenue, N.W.
                             Washington, D.C. 20037
                                January 18, 1999
Mr. Michael A. D'Amato
c/o The Corporate Executive Board Company
600 New Hampshire Avenue, NW
Washington, D.C.  20037
          Re:  Stock Option Agreement #1 and Stock Option Agreement #2, between
               The Corporate Executive Board Company and Michael D'Amato
               (collectively, the "Agreements")
Dear Mr. D'Amato
     Pursuant to Section 4(b)(iii) of the above referenced Agreements, which
provides me, as Chairman of the Board of The Corporate Executive Board Company,
with sole and absolute discretion to accelerate the dates on which Options
granted to you pursuant to the Agreements become exercisable in the event of an
Initial Public Offering, I hereby designate the date immediately before the
Initial Public Offering as the date on which you may first exercise all of your
Options.
     Capitalized terms used but not defined in this letter have the meanings
given them in the Agreement.
                                            Very truly yours,
   
   
                                            /s/ Harold L. Siebert
   
                                            Harold "Rusty" Siebert
                                            Chairman of the Board
                                            The Corporate Executive Board
                                            Company