ATG Achieves #5 Ranking On List of New England's 50 Fastest Growing Technology Companies; Recognition Attributed to 3918 Percent Revenue Growth Over Five Years.

Business/Technology Editors

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Sept. 14, 2000

Art Technology Group, Inc. (ATG) (Nasdaq:ARTG), a leading provider of customer relationship management and e-business solutions, today announced that it has achieved #5 ranking overall on the elite "New England Technology Fast 50" for 2000, a ranking of the 50 fastest-growing technology companies in the area.

ATG's increase in revenues of 3918 percent over the five-year period of 1995 to 1999 resulted in this placement on the Fast 50 for New England. This is the fourth year in a row that ATG has been named to the New England Technology Fast 50, and the first time it has ranked in the top five of fastest growing companies.

"This past year has been a truly rewarding one for ATG, and we're proud to once again achieve ranking on the list of fastest growing companies in New England," said Jeet Singh, CEO and co-founder of ATG. "ATG's #5 ranking on the New England Fast 50 list is yet another milestone for our company. We salute our fellow nominees for their successes and the contributions we've collectively made in our region and in our industries."

ATG's continued organic growth has resulted from increasing market acceptance and recognition of the ATG Dynamo(R) e-Business Platform, as well as rapid geographic growth and the ongoing success of ATG's proven channel strategy. Over the past year, ATG has aggressively increased employee headcount in 10 offices worldwide and announced the acquisitions of two service organizations in order to broaden the reach of systems integrators and partners. With over 180 signed partners, the company's growing relationships with its solutions and technology partners continue to drive ATG's business and enhance the growing reputation of ATG Dynamo as a leading platform for enterprise e-commerce and online customer management.

The recent launch of the ATG Dynamo 5 e-Business Platform, featuring scenario-driven personalization, demonstrates the innovative, thought leadership for which ATG is known. 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. ATG Dynamo 5's full-featured applications speed delivery of commerce and optimize personalization with breakthrough scenario-driven technology, while retaining the advantage of being a fully customizable, scalable and extensible platform. ATG continues to expand its list of customers that entrust ATG to provide the framework necessary to successfully deploy and manage their online customer relationships.

"ATG is one of only five companies that has made the list a remarkable four years in a row," said Steve DiPietro, a partner with Deloitte & Touche and co-chair of the 2000 New England Technology Fast 50 Program. "As one of the brand names of the new economy, ATG seems to keep doing all the right things in terms of both its products and its people, driving its significant growth year after year."

The Fast 50 program ranks New England's fastest-growing technology companies based on five-year revenue growth. The program is co-sponsored by the professional services firm of Deloitte & Touche and the law firm of Hale and Dorr LLP, in association with Mass High Tech, the Journal of New England Technology.

To qualify for the 2000 Fast 50 program, a company must have been in business a minimum of five years, with 1995 operating revenue of at least $50,000 and 1999 operating revenue of at least $1 million. It must be a technology company, strictly defined as one that develops proprietary technology that contributes to a significant portion of the company's operating revenues; manufactures a technology-related product; devotes a high percentage of effort to research and development of technology or uses proprietary technology to significantly improve the delivery of technology services. To qualify for the New England Technology Fast 50 program, the company must also be headquartered in the state of Massachusetts, Rhode Island, New Hampshire, Vermont or Maine.

All companies that participate in the New England program are also entered into Deloitte & Touche's national recognition program, the Technology Fast 500. For more information on the national Technology Fast 500 or the regional Technology Fast 50 programs, please visit www.fast500.com.

For more information on Deloitte & Touche, visit their web site at www.us.deloitte.com. For more information on Hale and Dorr LLP, visit their web site at www.haledorr.com. For more information on Mass High Tech, visit their web site at www.masshightech.com.

About Art Technology Group

Art Technology Group, Inc. 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 1000 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.

The Dynamo solution is designed to provide businesses with the core platform and applications required to develop and deploy personalized, scalable and reliable e-commerce Web sites. Dynamo is licensed to over 400 customers including 3M, BabyCenter, BMG Direct, Eastman Kodak, Informix, J. Crew, Network Solutions, Sun Microsystems, Target Corporation and TheStreet.com. The company is headquartered in Cambridge, Mass., with additional locations throughout North America, Europe and Asia Pacific.

About Deloitte & Touche

Deloitte & Touche, one of the nation's leading professional services firms, provides assurance and advisory, tax, and management consulting services through 30,000 people in more than 100 U.S. cities. The firm is dedicated to helping its clients and its people excel. Known as an employer of choice for its innovative human resources programs, Deloitte & Touche has been recognized as one of the "100 Best Companies to Work for in America" by Fortune magazine for three consecutive years. Deloitte & Touche is part of Deloitte Touche Tohmatsu, one of the world's leading professional services firms, with more than 90,000 people in over 130 countries. For more information, please visit Deloitte & Touche's web site at www.us.deloitte.com.

About Hale and Dorr LLP

Hale and Dorr LLP is a nationally preeminent high-technology law firm, with over 400 attorneys and offices in Boston, Washington, D.C., Reston, Va., and New York. The firm has a strong reputation for advising and guiding emerging growth companies, especially those in the software, telecommunications and biotechnology industries. For more information, visit the firm's web site at www.haledorr.com.

About Mass High Tech

Mass High Tech, The Journal of New England Technology is a weekly technology journal serving the executives and management-level engineers of New England's innovation and technology industries.

The journal's writers search out innovation and companies working on the "bleeding" edge and then report on their work and its marketplace applications before they make mainstream business news. Most importantly, Mass High Tech profiles and follows the people driving New England's innovation economy. With weekly readership of over 46,000, Mass High Tech's penetration into New England's technology community is unmatched.

Dynamo is a registered trademark of Art Technology Group.

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 company's growth may not continue at past rates and may not qualify it to be included in future award; unrealistic customer evaluations; 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.