Collaboration Agreement

Re: Collaboration Agreement, Dated as of February 6, 2007, by and Between the Corporate Executive Board Company and the Advisory Board Company (The Collaboration Agreement)

Exhibit 10.1
         
The Advisory Board Company    
 
       
2445 M. STREET, NW
       
WASHINGTON, DC 20037
       
 
       
TELEPHONE 202-266-6696
      Robert Musslewhite
FACSIMILE 202-266-6633
  February 4, 2010   Chief Executive Officer
Thomas L. Monahan, III
Chairman of the Board and Chief Executive Officer
The Corporate Executive Board Company
1919 North Lynn Street
Arlington, VA 22209
      Re:   Collaboration Agreement, dated as of February 6, 2007, by and between The Corporate Executive Board Company and The Advisory Board Company (the “Collaboration Agreement”)
Dear Tom:
     This letter confirms that The Corporate Executive Board Company (“CEB”) and The Advisory Board Company (“ABCO”) have agreed to extend the Initial NP Term and the Initial EC Term (as such terms are defined in the Collaboration Agreement) through February 5, 2012 as contemplated by Sections 3.3(a) and 3.4(a) of the Collaboration Agreement, respectively, effective as of February 4, 2010.
     Please indicate your agreement with the foregoing by signing and returning one copy of this letter to my attention, which shall constitute CEB’s and ABCO’s agreement with respect to the subject matter hereof.
     
 
  Very truly yours,
 
  -s- Robert W. Musslewhite
 
  Robert W. Musslewhite
 
  Chief Executive Officer
ACCEPTED AND AGREED:
THE CORPORATE EXECUTIVE BOARD COMPANY
         
By:
  -s- Thomas L. Monahan, III
 
   
 
  Thomas L. Monahan, III    
 
  Chairman of the Board and Chief Executive Officer