EXHIBIT 23.1

INDEPENDENT AUDITORS' CONSENT

We consent to the incorporation by reference in Registration Statements Nos.
333-16905, 333-22749, 333-96393, 333-38626, 333-99749, and 333-99751 of
Forrester Research, Inc. on Form S-8 of our report dated March 11, 2004, which
report expresses an unqualified opinion and includes explanatory paragraphs
relative to the adoption of Statement of Financial Accounting Standards No. 142,
"Goodwill and Other Intangible Assets" and the application of procedures
relating to certain disclosures of financial statement amounts related to the
2001 financial statements that were audited by other auditors who have ceased
operations, relating to the consolidated financial statements of Forrester
Research, Inc. as of and for the years ended December 31, 2003 and 2002,
appearing in this Annual Report on Form 10-K of Forrester Research, Inc. for the
year ended December 31, 2003.

/s/ Deloitte & Touche LLP

Boston, Massachusetts
March 11, 2004