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                            INDEMNIFICATION AGREEMENT
                            -------------------------

     This Indemnification Agreement is made and entered into this 28th day of
February, 2000 ("AGREEMENT"), by and between Forrester Research, Inc., a
Delaware corporation (the "COMPANY") and the persons listed as Selling
Stockholders on the signature pages hereto (the "Selling Stockholders". Unless
otherwise defined herein, terms defined in the Underwriting Agreement, dated as
of February 22, 2000 (the "UNDERWRITING AGREEMENT") among the Company, the
Selling Stockholders and the other stockholders of the Company party thereto,
Goldman, Sachs & Co., Adams, Harkness & Hill, Inc., Thomas Weisel Partners LLC,
FAC/Equities, a division of First Albany Corporation and William Blair &
Company, L.L.C., as representatives of the several underwriters (collectively,
the "UNDERWRITERS") and used herein shall have the meanings given to them in the
Underwriting Agreement.

                                    RECITALS

     WHEREAS, the Company has filed a Registration Statement on Form S-3 (File
No. 333-95663) (the "REGISTRATION STATEMENT") with the Securities and Exchange
Commission to register 3,269,450 shares of common stock, $0.01 per value per
share ("Common Stock"), of the Company;

     WHEREAS, pursuant to the Underwriting Agreement, the Selling Stockholders,
other stockholders of the Company and the Company will sell Shares of Common
Stock to the Underwriters; and

     WHEREAS, under the Underwriting Agreement, the Selling Stockholders are
obligated to indemnify the Underwriters under the circumstances set forth
therein and the Company wishes to indemnify the Selling Stockholder for certain
of such indemnification obligations.

     NOW, THEREFORE, in consideration of the premises and the covenants
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and the Selling
Stockholders do hereby covenant and agree as follows:

                                    AGREEMENT

     1.   DEFINITIONS. Terms defined in the Underwriting Agreement and not
otherwise defined herein are used herein with the meanings so defined.

     2.   INDEMNIFICATION. The Company shall indemnify and hold harmless each of
the Selling Stockholders against any losses, claims, damages or liabilities
(collectively, the


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 "DAMAGES") for which such Selling Stockholder indemnifies any Underwriter
pursuant to Section 8 of the Underwriting Agreement and will reimburse each
Selling Stockholder for any legal or other expenses reasonably incurred by such
Selling Stockholder in connection with defending any action or claim for which
such Selling Stockholder is entitled to indemnification hereunder; PROVIDED,
HOWEVER, that the Company shall not be required to indemnify and hold harmless
any Selling Stockholder for such Damages to the extent that such Damages arise
out of or are based upon an untrue statement or alleged untrue statement or
omission or alleged omission made in any Preliminary Prospectus, the
Registration Statement or the Prospectus or any amendment or supplement thereto
in reliance upon and in conformity with written information furnished by such
Selling Stockholders to the Underwriters through Goldman, Sachs & Co. expressly
for use therein.

     3.   PROCEDURE. Promptly after a Selling Stockholder has received notice of
or has knowledge of any claim by an Underwriter for which the Company is
obligated to indemnify such Selling Stockholder pursuant to Section 2 above (a
"CLAIM"), such Selling Stockholder shall, as a condition precedent to a Claim
with respect thereto being made against the Company, give the Company written
notice of such Claim. Such notice shall state the nature and the basis of such
Claim and a reasonable estimate of the amount thereof. The Company shall have
right to defend and settle, at its own expense and by its own counsel, any such
Claim. Such Selling Stockholder shall cooperate with the Company and its counsel
in the defense thereof and in any settlement. If the Company desires to accept a
final and complete settlement of any such Claim and such Selling Stockholder
unreasonably refuses to consent to such settlement, then the Company's liability
under Section 2 with respect to such Claim shall be limited to the amount so
offered in settlement by such Underwriter and such Selling Stockholder shall
reimburse the Company for any additional costs of defense which it subsequently
incurs with respect to such Claim.

     4.   GENERAL PROVISIONS.

          (a)  AMENDMENT. This Agreement may not be amended except by an
instrument in writing signed by the parties hereto.

          (b)  SEVERABILITY. If any term or other provision of this Agreement is
invalid, illegal or incapable of being enforced by any rule of law, or public
policy, all other conditions and provisions of this Agreement shall nevertheless
remain in full force and effect so long as the economic or legal substance of
the transactions contemplated hereby is not affected in any manner adverse to
any party. Upon such determination that any term or other provision is invalid,
illegal or incapable of being enforced, the parties hereto shall negotiate in
good faith to modify this Agreement so as to effect the original intent of the
parties as closely as possible in an acceptable manner to the end that the
transactions contemplated hereby are fulfilled to the fullest extent possible.

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          (c)  ASSIGNMENT. No party may assign this Agreement or delegate its
obligations hereunder without, in the case of the Company, each of the Selling
Stockholders, and, in the case of a Selling Stockholder, without the consent of
the Company.

          (d)  PARTIES IN INTEREST. This Agreement shall be binding upon and
inure solely to the benefit of each party hereto and its successors and
permitted assigns and nothing in this Agreement, express or implied, is intended
to or shall confer upon any other person any right, benefit or remedy of any
nature whatsoever under or by reason of this Agreement.

          (e)  GOVERNING LAW. This Agreement has been executed as an agreement
under seal and shall be governed by, and construed in accordance with, the laws
of The Commonwealth of Massachusetts without giving effect to the conflict of
laws principles thereof.

          (f)  COUNTERPARTS. This Agreement may be executed in one or more
counterparts, and by the different parties hereto in separate counterparts, each
of which when executed shall be deemed to be an original but all of which taken
together shall constitute one and the same agreement.

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           IN WITNESS WHEREOF, the parties hereto have executed this Agreement
on the day and year first above written.

                                         FORRESTER RESEARCH, INC.

                                         By:  /s/ George F. Colony
                                             -------------------------------
                                              Name:
                                              Title:

                                         Selling Stockholders:

                                         /s/ Mary A. Modahl
                                         -----------------------------------
                                         Mary A. Modahl

                                         /s/ William M. Bluestein
                                         -----------------------------------
                                         William M. Bluestein, Ph.D.

                                         /s/ Susan M. Whirty
                                         -----------------------------------
                                         Susan M. Whirty

                                         /s/ Emily Nagle Green
                                         -----------------------------------
                                         Emily Nagle Green

                                         /s/ Joel Blenner
                                         -----------------------------------
                                         Joel Blenner

                                         /s/ John W. Boynton
                                         -----------------------------------
                                         John W. Boynton

                                         /s/ Stanley Dolberg
                                         -----------------------------------
                                         Stanley Dolberg

                                         /s/ Timothy M. Riley
                                         -----------------------------------
                                         Timothy M. Riley

                                         /s/ Richard C. Belanger
                                         -----------------------------------
                                         Richard C. Belanger

                                         /s/ Robert M. Galford
                                         -----------------------------------
                                         Robert M. Galford