Forrester Research, Inc. (Nasdaq: FORR), a leading provider of research and analysis on emerging technologies, today announced revised financial guidance for the first quarter of 2003, which includes the post-acquisition financial effect of Giga Information Group, Inc. Forrester completed the acquisition of Giga on February 28, 2003, and Giga is now a wholly owned subsidiary of Forrester.

The following guidance is based on current expectations and industry trends. These statements are forward-looking and actual results may differ materially. For the first quarter ending March 31, 2003, Forrester anticipates revenues of approximately $23.0 million to $25.0 million, a pro forma operating margin of approximately 8 percent to 10 percent, and pro forma diluted EPS of approximately $0.08 to $0.10. Pro forma operating margin and EPS guidance exclude amortization of intangible assets related to the acquisition.

In conjunction with the acquisition of Giga, Forrester eliminated 56 North American-based positions, all of which are related to Giga’s general and administrative responsibilities, and will be closing Giga’s offices in Cambridge and Norwell, Mass.

“As reflected in our revised first-quarter guidance, we expect the acquisition to be accretive to operating margin and earnings per share on a pro forma basis,” stated George F. Colony, chairman of the board and chief executive officer. “The integration process is progressing at a rapid pace, and we have already seen positive results for clients as Forrester and Giga employees begin working together.”

The company expects to report its first-quarter 2003 results and plans to provide guidance for the full-year 2003 on April 30, 2003.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, Forrester’s financial guidance for the first quarter of 2003 and the statements about its acquisition of Giga. These statements are based on Forrester’s current plans and expectations and involve risks and uncertainties that could cause actual future activities and results of operations to be materially different from those set forth in the forward-looking statements. Important factors that could cause actual future activities and results to differ include, among others, Forrester’s ability to anticipate business and economic conditions, market trends, competition, the need to retain professional staff, possible variations in Forrester’s quarterly operating results, Forrester’s ability to successfully integrate Giga into Forrester’s operations, Forrester’s dependence on renewals of its membership-based research services and on key personnel, and risks associated with Forrester’s ability to offer new products and services. Forrester Research undertakes no obligation to update publicly any forward-looking statements, whether as a result of new information, future events, or otherwise. For further information, please refer to Forrester¿s reports and filings with the Securities and Exchange Commission.