Royal Mail Re-Commits to ATG to Enhance Customer Experiences

ATG's Wisdom-enabled solutions will allow Royal Mail to provide a superior level of online service

CAMBRIDGE, Mass., March 6, 2006 - ATG (Art Technology Group, Inc. NASDAQ: ARTG), the software provider behind the most consistent and relevant marketing, commerce, and customer service experiences, today announced that Royal Mail has purchased, and will be using more elements of the ATG Customer Experience Platform as the company increases efforts to improve service to customers and provide them with relevant and rich customer service experiences across its brands - Royal Mail, Parcelforce Worldwide, and Post Office(TM). Royal Mail Group plc is a public limited company wholly owned by the British Government, with annual sales in excess of #8 billion and 196,000 employees.

ATG will help Royal Mail to better serve and communicate more effectively with its customers (whether via the web, e-mail, mobile devices, call centers or in person at its offices) using elements of the ATG Wisdom-enabled Service Suite. Royal Mail currently uses ATG Commerce and ATG Content Administration to market and sell to customers. In the longer term, the ATG Service Suite will ensure Royal Mail has every component in place to use best-of-breed applications across the full spectrum of the customer lifecycle, including marketing, sales and customer service, which ultimately delivers a superior customer experience.

"I mproving our service to customers is a key priority for Royal Mail," said Dennis Greene, head of operations for Royal Mail Group E-Business. "By using our knowledge about the customer to make every contact with them productive and relevant, we have the opportunity to derive more value from those exchanges. We believe that the ATG Wisdom strategy and suite of marketing, commerce, and service products will enable us to reach our customers on a personal level to build stronger relationships and offer enhanced value."

"Customer-centric companies such as Royal Mail recognize that they need to use every customer touchpoint to encourage interest, drive sales, satisfy a need or demonstrate commitment to the relationship," said Cliff Conneighton, senior vice president of marketing, ATG. "Further, Royal Mail understands the need to differentiate the customer base, and move away from the traditional 'one-size-fits-all' approach to online commerce and service. To succeed, companies and organizations need to strategically invest in various customer segments, with the goal of matching the level of service to customer value. With ATG, Royal Mail is able to do this, and ultimately reduce costs and increase customer loyalty and satisfaction."

About ATG

ATG (Art Technology Group, Inc., NASDAQ: ARTG) makes the software that the world's most customer-conscious companies use to create a more relevant and consistent customer experience, throughout the marketing, commerce, and service lifecycle, and across the Web, e-mail, call center, and mobile channels. Offering an alternative to the traditional silo-based approach to customer-facing applications, ATG's solutions power over 600 major brands, including A&E Networks, Airbus, American Airlines, American Eagle Outfitters, Best Buy, Boeing, Cingular Wireless, DirecTV, France Telecom, Friends Provident, Hewlett-Packard, Hotels.com, Hyatt Hotels, HSBC, InterContinental Hotels Group, Kingfisher, Louis Vuitton, Merrill Lynch, Neiman Marcus, Philips, Procter & Gamble, Symantec, T-Mobile, Target, USAA, US Army, US Navy, Warner Music, and Wells Fargo. The company is headquartered in Cambridge, Massachusetts, with additional locations throughout North America, Europe, and Asia. For more information about ATG, please visit www.atg.com.

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(c) 2006 Art Technology Group, Inc. ATG and Art Technology Group are registered trademarks of Art Technology Group, Inc. All other product names, service marks, and trademarks mentioned herein are trademarks of their respective owners.

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 their periodic reports and registration statements filed with the Securities and Exchange Commission at www.sec.gov . Risk factors related to the subject matter of this press release include the possibility that the ATG product deployment will not be successful, on time or significantly enhance the user's Internet experience or will not increase customer revenue across brands; that those customers leveraging ATG won't have the opportunity to increase revenue and decrease future costs; the need to adapt to rapid changes so products do not become obsolete; the possibility of errors in ATG's software products; the possibility that the solution will not make customer implementations faster or more flexible or permit the customer to meet its customer-facing or infrastructure requirements; that the ATG product will not continue to be integrated with third party applications servers or will not support all Web services enabled systems; that ATG's product strategy may change in the future; and the risks and costs of intellectual property litigation. ATG undertakes no obligation to update any of the forward-looking statements after the date of this press release.

Tucker Walsh
ATG
+1.617.386.1159
twalsh@atg.com

Jesse Ciccone
Matter Communications
+1.978.499.9250 x230
atg@matternow.com