ATG Holds First Place Ranking Among Internet Commerce Platform Vendors From Forrester Research.

Business/Technology Editors

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Nov. 29, 2000

Forrester's eBusiness TechRankings(TM) Cites J2EE Certification,

Integration Capabilities, and Channel Partnerships as Key

Differentiators for ATG 

Art Technology Group, Inc. ("ATG") (Nasdaq: ARTG), developer of the ATG Dynamo(R) e-Business Platform for online customer management, today announced that Forrester Research, Inc. (Nasdaq: FORR) currently ranks ATG first among Internet commerce platform vendors, following its research and testing of 10 market-leading vendors.

Forrester's eBusiness TechRankings contain detailed, objective research to help companies select and implement the best technology for their eBusiness initiatives. eBusiness TechRankings'(TM) continuous research combines product testing results and market analysis to help firms understand rapidly changing technology markets, accelerate and improve product selection, and effectively gauge implementation costs and effort.

According to Forrester's analysis, "ATG's Dynamo Commerce Suite is J2EE-certified and exposes its services as Java APIs. This fact lets developers easily extend Dynamo-based commerce sites and integrate third-party components. To help, (ATG) expertly leverages systems integrators through formal training and mentoring programs."

"ATG is thrilled to be in first place in Forrester's research and testing of commerce platforms," said Joe Chung, chief technology officer for ATG. "The findings reinforce ATG's belief that we have made the right choices in product development, primarily by listening to our customers in order to understand their needs and how they will change with shifting business trends and new, emerging technologies."

With ATG Dynamo 5, ATG is a pioneer in real-time scenario-driven personalization of the online customer experience - from customer acquisition and behavior to retention and loyalty - to increase lifetime customer value. The full-featured ATG Dynamo 5 speeds delivery of commerce and optimizes personalization with innovative scenario-driven technology, while retaining the advantage of being a fully customizable, scalable and extensible platform. ATG continues to expand the list of customers that entrust ATG to provide the framework necessary to successfully deploy and manage their online customer relationships.

About ATG

ATG is a leading provider of online customer relationship management and electronic commerce products and services. ATG offers an integrated suite of Java(TM) application server-based products and services, as well as related application development, integration and support services. The ATG Dynamo(R) e-Business Platform enables Global 2000 enterprises, as well as new businesses using the Internet as their primary business channel, to understand, manage and build their online customer relationships and to more effectively market, sell and support their products and services over the Internet.

With its network of more than 225 solution partners, ATG has delivered e-business solutions to over 530 companies worldwide including 3M, Aetna Services, Inc., American Airlines, Blockbuster, BabyCenter, BMG Direct, ChipCenter, Eastman Kodak, HSBC, Herman Miller, J. Crew, Network Solutions, Sun Microsystems, and Target. The company is headquartered in Cambridge, Massachusetts with additional locations throughout North America, Europe, Asia and Australia.

Dynamo, ATG and Art Technology Group are registered trademarks of Art Technology Group, Inc.

This press release contains forward-looking statements for purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. These statements involve known and unknown risks and uncertainties that may cause ATG's actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by such forward-looking statements. Important risk factors affecting ATG's business generally may be found in ATG's periodic reports and registration statements filed with the Securities and Exchange Commission. Risk factors related to the subject matter of this press release include the possibility that the Forrester report misstated or misunderstood the features and functions of Dynamo; that future additions or changes to the Dynamo product suite will not keep pace with the needs of the e-commerce market; that Art Technology Group's products will not receive similar rankings in the future; that the company's growth may not continue at past rates and may not qualify it to be included in future evaluations; unrealistic customer expectations; the need to adapt to rapid changes so products do not become obsolete; the possibility of errors in ATG's software products; non-responsiveness of the market to such awards; and the costs and risks associated with intellectual property infringement and litigation. ATG undertakes no obligation to update any of the forward-looking statements after the date of this press release.