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                                                                    EXHIBIT 10.3


                            NON-COMPETITION AGREEMENT


        THIS NON-COMPETITION AGREEMENT (this "Agreement"), is entered into
effective upon the initial public offering of The Advisory Board Company's
common stock, by and between The Advisory Board Company, a Maryland corporation,
including its subsidiaries, successors and assigns (collectively, "ABC"), and
David G. Bradley, including his successors, assigns and any entity controlled by
him (collectively, "Bradley").

        WHEREAS, ABC and Bradley desire to enter into an agreement to place
certain limitations on competition between Bradley and ABC;

        WHEREAS, Bradley has resigned as sole director and an officer of ABC;
and

        WHEREAS, Bradley plans to sell shares of ABC's common stock owned by him
in an initial public offering of ABC's common stock.

        NOW, THEREFORE, in consideration of the premises and covenants contained
herein and intending to be legally bound hereby ABC and Bradley agree as
follows:

1.      DEFINITIONS.

        (a)    "Covered Services" shall mean membership based products and
               services substantially similar to the products and services
               provided by ABC as of the date of this agreement.

        (b)    "Health Care Company" shall mean any company or institution, or
               any division or subsidiary of any company or institution, that
               is principally engaged in the health care industry, which shall
               include providers of patient care (such as hospitals, outpatient
               facilities, home health agencies and relevant government
               agencies), providers of medical professional  services (such as
               physician and nursing services and physician  practice
               management companies) and other types of health  care business
               (such as pharmaceutical companies; medical supply  and equipment
               companies; technology, software, communications, financing and
               services vendors selling predominantly to health  care
               companies; companies providing health insurance; and  managed
               care companies).

2.      NON-COMPETITION. For a period of five years after the date hereof,
Bradley shall not offer or sell Covered Services to any Health Care Company.
Notwithstanding the forgoing, Bradley may sell to any entity:

        (a)   software development products and services;

        (b)   magazines, newspapers and news services;

        (c)   advertising for its publications, news and on-line services;

        (d)   products and services that are specifically addressed to and deal
              with advertising and promotion activities by companies,
              institutions and advertising agencies, provided that such
              products and services are offered only to the offices and
              divisions of companies, institutions or advertising agencies that
              are responsible for the placement or designing of advertisements;
              and

        (e)   products and services that are specifically addressed to and deal
              with government relations and lobbying activities by companies
              and institutions, provided that such products and services are
              offered only to the offices and divisions of companies or
              institutions that are responsible for government relations and
              lobbying.

3.      SOLICITATION OF EMPLOYEES. For a period of three years after the date
hereof, Bradley shall not recruit or employ any person who is at the time of
such recruitment an employee of ABC, or who was employed by ABC at any time
during the 24-month period preceding the date of such recruitment or employment,
unless ABC's chief executive officer consents to such recruitment and
employment.

4.      FURTHER ASSURANCES. ABC and Bradley agree that at any time and from time
to time, upon written request, they will execute and deliver such further
documents and do such further acts and things as may be reasonably requested in
order to effectuate the purposes of this Agreement and the transactions
contemplated hereby.
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5.      AMENDMENT. This Agreement may be amended, restated or terminated upon
the approval of Bradley and ABC's Board of Directors.

6.      GOVERNING LAW. This Agreement will be governed by and construed in
accordance with the internal laws of the State of Delaware (excluding its choice
of law rules).

7.      ARBITRATION. The parties shall endeavor to settle all disputes by
amicable negotiations. Any claim, dispute, disagreement or controversy that
arises among the parties ("Disputed Matter") relating to this Agreement that is
not amicably settled shall be referred to and settled by arbitration
administered by the American Arbitration Association in accordance with the
Expedited Procedures of the Commercial Arbitration Rules of the American
Arbitration Association (the "AAA Rules") by a single arbitrator who is mutually
agreeable to the parties. If the parties are unable to agree upon an arbitrator,
one arbitrator shall be selected in accordance with the AAA Rules. All
proceedings in any such arbitration shall be conducted in Washington, D.C. Each
party to such arbitration proceeding shall bear its respective costs, fees and
expenses in connection with such arbitration. Upon a final determination by the
arbitrator with respect to the Disputed Matter, the arbitrator shall notify the
parties (such notice being the "Arbitration Order"). Any judgment on the award
rendered by the arbitrator may be entered in any court having jurisdiction
thereof. The jurisdiction of such arbitrator shall be exclusive as to disputes
among the parties relating to this Agreement and each of the parties agrees that
this Agreement to arbitrate shall be specifically enforceable under the laws of
the respective domiciliary jurisdictions of the parties. Neither of the parties
shall have the right to appeal the Arbitration Order or otherwise to submit a
dispute relating to this Agreement to a court of law.

8.      COUNTERPARTS. This Agreement may be executed in counterparts, each of
which will constitute an original and all of which will be one and the same
document.

                          [The signature page follows.]


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        IN WITNESS WHEREOF, the parties have executed this Agreement effective
as of the date first written above.


                                            THE ADVISORY BOARD COMPANY



                                            By:    /s/ FRANK J. WILLIAMS
                                                -------------------------------
                                            Name:  Frank J. Williams
                                            Title: Chief Executive Officer



                                            /s/ DAVID G. BRADLEY
                                            -----------------------------------
                                            David G. Bradley




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