READING, UK & DORTMUND, Germany--June 14, 2006--ATG (Art Technology Group, Inc. NASDAQ: ARTG), whose technology powers outstanding e-commerce sites and corresponding e-marketing and customer service solutions, on premise and on demand, today announced that it has signed a wide-ranging partnership agreement with MATERNA Information & Communications, the leading German independent solutions provider of IT service management, customer service management and government services. As a preferred ATG partner MATERNA is the first solutions provider in Germany who will support the new ATG product portfolio.

The partnership will strengthen both companies' positions within the German marketplace, offering German businesses a complete range of technology solutions that will help increase revenues and maximise sales. In previous projects both companies have already worked together very successfully in the field of e-commerce solutions.

Peter Ford, ATG Alliances Director, Europe, Middle East & Africa, said of the agreement: "In order to achieve an integrated approach to customer experience management, companies need CRM and customer experience solutions that manage the complete lifecycle, allowing them to identify their most profitable customer relationships and opportunities, and then to provide marketing offers, commerce options, and e-service that helps companies retain and grow those relationships. The combination of ATG and MATERNA's technology into a complete, robust solution provides businesses with a formidable tool with which to achieve this goal. It also provides superior customer satisfaction levels, improved employee efficiency and lower operating costs."

Dr. Winfried Materna, Chief Executive Officer (CEO), MATERNA, said: "We are delighted to have signed this agreement with ATG. Its business focus is entirely complementary to our own solutions portfolio in the customer service management and e-business solutions arena. With the resurgence of high-end requirements for this sort of technology and most notably e-commerce and customer care, this agreement will position both ATG and MATERNA at the forefront of this market in Germany."

With this partnership MATERNA continues to expand its customer service management strategy: Customer service management is the comprehensive management of customer relations in a service environment and aims to improve the quality and efficiency of service processes. It includes all customer contacts, complaints, and up to distribution logistics. In the field of customer service management MATERNA provides strategy and process consulting as well as analysis, conceptual design, implementation and integration.

About ATG

ATG (Art Technology Group, Inc., NASDAQ: ARTG) delivers innovative software to help high-end consumer-facing companies create a richer, more adaptive interactive experience for their customers and partners online and via other channels. ATG has delivered category-leading e-business solutions to many of the world's best-known brands including Best Buy, Kingfisher, Neiman Marcus, Target, Friends Provident, Merrill Lynch, Wells Fargo, A&E Networks, Warner Music, AT&T Wireless, France Telecom, Philips, Procter & Gamble, Hewlett-Packard, American Airlines, InterContinental Hotels Group, US Army, and US Federal Aviation Administration. 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.

About MATERNA

The MATERNA Group is among the leading independent software companies in Europe's information and communication technology sector. MATERNA provides solutions for optimising IT-supported business processes in companies and the public sector. The company's focus is on IT service management, customer service management and government services. The service package consists of modules for process and technology consulting, conceptual design, implementation and training. Founded in 1980 in Germany, MATERNA currently employs approx. 1,200 employees worldwide. In the 2005 business year, the group achieved revenues of EUR 144 million. In Northern Europe the company has branches in Denmark, Finland and Sweden. For more information about MATERNA, please visit www.materna.com.