UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): APRIL 1, 2002 FORRESTER RESEARCH, INC. (Exact name of registrant as specified in its charter) DELAWARE 000-21433 04-2797789 (State or other jurisdiction of (Commission file number) (I.R.S. Employer incorporation or organization) Identification No.) 400 TECHNOLOGY SQUARE 02139 CAMBRIDGE, MASSACHUSETTS (Address of principal executive offices) (Zip Code) (617) 613-6000 (Registrant's telephone number, including area code) NOT APPLICABLE (Former name or former address, if changed since last report)

ITEM 4. CHANGES IN REGISTRANT'S CERTIFYING ACCOUNTANT. On April 1, 2002, the Audit Committee of Forrester Research, Inc. ("Forrester") recommended, and the Board of Directors of Forrester decided, to no longer engage Arthur Andersen LLP ("Andersen") as Forrester's independent public accountants and engaged Deloitte & Touche LLP to serve as Forrester's independent public accountants for the fiscal year 2002. Andersen's reports on Forrester's consolidated financial statements for each of the years ended December 31, 2001 and December 31, 2000 did not contain an adverse opinion or disclaimer of opinion, nor were they qualified or modified as to uncertainty, audit scope, or accounting principles. During the years ended December 31, 2001 and December 31, 2000 and through the date hereof, there were no disagreements with Andersen on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedure which, if not resolved to Andersen's satisfaction, would have caused it to make reference to the subject matter in connection with its report on Forrester's consolidated financial statements for such years. There were no reportable events as defined in Item 304(a)(1)(v) of Regulation S-K. Forrester has provided Andersen with a copy of the foregoing disclosures. A letter from Andersen addressed to the Securities and Exchange Commission is included as Exhibit 16.1 to this Current Report on Form 8-K and states that Andersen agrees with such disclosure. During the years ended December 31, 2001 and December 31, 2000 and through the date hereof, Forrester did not consult Deloitte & Touche with respect to the application of accounting principles to a specified transaction, either completed or proposed, or the type of audit opinion that might be rendered on Forrester's consolidated financial statements, or any other matter that was either the subject of a disagreement (as defined in Item 304(a)(1)(iv) of Regulation S-K) or a reportable event (as described in Item 304(a)(1)(v) of Regulation S-K). ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS. (c) EXHIBITS. EXHIBIT NUMBER DESCRIPTION OF EXHIBIT - ------- ---------------------- 16.1 Letter from Arthur Andersen LLP to the SEC, dated April 5, 2002, regarding change in certifying accountant. 99.1 Press release of Forrester Research, Inc. dated April 3, 2002.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Forrester Research, Inc. Date: April 5, 2002 By: /s/ WARREN HADLEY -------------------------------------- Warren Hadley Chief Financial Officer and Treasurer (Principal Financial and Accounting Officer)

EXHIBIT INDEX EXHIBIT NUMBER DESCRIPTION OF EXHIBIT - ------- ---------------------- 16.1 Letter from Arthur Andersen LLP to the SEC, dated April 5, 2002, regarding change in certifying accountant. 99.1 Press release of Forrester Research, Inc. dated April 3, 2002.

EXHIBIT 16.1 [ANDERSON LOGO] April 5, 2002 ARTHUR ANDERSEN LLP Office of the Chief Accountant 225 Franklin Street Securities and Exchange Commission Boston MA 02110-2812 450 Fifth Street, N.W. Washington, D.C. 20549 Tel 617 330 4000 Fax 617 453 0731 Dear Sir/Madam: We have read paragraphs two and three of Item 4 included in the Form 8-K dated April 5, 2002 of Forrester Research, Inc. filed with the Securities and Exchange Commission and are in agreement with the statements. Very truly yours, /s/ Arthur Andersen LLP - ------------------------------- Arthur Andersen cc: Mr. Warren Hadley, CFO Forrester Research, Inc.

Exhibit 99.1 FOR IMMEDIATE RELEASE FORRESTER RESEARCH APPOINTS DELOITTE & TOUCHE LLP AS NEW AUDITOR CAMBRIDGE, Mass., April 3, 2002 . . . Forrester Research, Inc. (Nasdaq: FORR), a leading provider of research and analysis on emerging technologies, today announced the appointment of Deloitte & Touche LLP as its independent auditor for fiscal year 2002. Arthur Andersen LLP had previously served as Forrester's independent auditor. The appointment of Deloitte & Touche was made after careful consideration and an extensive evaluation process by Forrester's Board of Directors, Audit Committee, and management team. "Although Andersen has provided excellent service in the past, we think this decision is in the best interest of the company and its shareholders," said Warren Hadley, chief financial officer. "We look forward to our working relationship with Deloitte & Touche." Forrester Research is a leading emerging-technology research firm providing data and analysis that defines the impact of technology change on business. Forrester's WholeView(TM) Research, Strategic Services, and Events help Global 3,500 clients understand how technology change affects their customers, strategy, and technology investment. Established in 1983, Forrester is headquartered in Cambridge, Mass. For additional information, visit www.forrester.com. - ### - Contact: Kimberly Maxwell Investor Relations Manager Forrester Research, Inc. +1 617/613-6234 (C)2002, Forrester Research, Inc. All rights reserved. Forrester and WholeView are trademarks of Forrester Research, Inc.