ATG Announces Virtual Classroom Training; ATG Education Courses Now Available Online.

Business Editors/Education Writers/High-Tech Writers

CAMBRIDGE, Mass.--(BUSINESS WIRE)--May 13, 2004

ATG (Art Technology Group Inc., NASDAQ: ARTG), the software provider behind the Web's richest customer experiences, today announced the rollout of the ATG Virtual Classroom, a new delivery mechanism for existing ATG education courses. A wide array of ATG courses can now be delivered live via the Web by ATG Certified Instructors, using the same course material that is used in the physical classroom. Students will still have hands-on training and access to an instructor for the same number of hours as in a physical classroom (16 hours for a 2-day class), but now it can be in a virtual lab environment.

Instructors still perform live product demonstrations while students can ask questions at any time by electronically "raising their hand." Instructors can also "peer over the shoulder" of students while they are working on hands-on exercises, to help troubleshoot and offer instruction. Students are provided with all of the same resources they would receive in a physical classroom - a complete student guide, lab guide and student files.

"Time is scarce and travel budgets are down, so we wanted to provide a solution to help people get the training they need to get the most out of ATG technology," said Pat Durante, senior manager of training at ATG. "Users of ATG technology need to have access to the right training, at the right time to complete projects on their timetable and within budget. The ATG Virtual Classroom simulates the experience of our education centers around the world while offering convenience and, most importantly, access to the knowledge our customers and partners need to manage their business."

ATG encourages anyone interested in the Virtual Classroom program to attend a free one hour test drive session. Separate topics for business and technical users are offered monthly. For more information, or to register for a session, please visit http://www.atg.com/en/education/virtual.jhtml.

Other benefits of the ATG Virtual Classroom:

-- Allows organizations to deepen the skills of its employees. By

training virtually, companies will be able to afford

additional training since Virtual Classroom courses don't

incur the travel cost or time away from the office.

-- Provides hands-on access to ATG products with no software

installation required.

-- Makes it easy and convenient to consume ATG training anywhere

users have an Internet connection - in the office, at home, or

at a client site.

-- Half day training schedules enable students to learn while

still meeting project deadlines.

-- Supports both technical and business users.

ATG Education collaborates with Toolwire (www.toolwire.com) and leverages their LiveLabs ILT service, which provides a seamless virtual lab environment for ATG's online test drive sessions and education courses.

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 A&E Television, Aetna Services, Inc., Alcatel, American Airlines, Barclays Global Investors, Best Buy, BMG Direct, Eastman Kodak, Ford Motor Credit, HSBC, Hyatt, J.Crew, Merrill Lynch, Newell Rubbermaid, Target, U.S. Army, Walgreen Company 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.

(C)2004 Art Technology Group, Inc. ATG and Art Technology Group are registered trademarks of Art Technology Group, Inc., and ATG Adaptive Customer Assistance is its trademark. 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 but are not limited to the following possibilities: that technical delays, interruptions, cancellations, glitches, or unavailability, including such as affect the Web generally, may, from time to time, affect the delivery of ATG Virtual Classrooms; that user demand and course logistics may, from time to time, alter or affect a class offering; that ATG's product strategy or offerings may change in the future requiring user re-education. ATG does not by this release make any representations or warrant in any manner the Virtual Classroom, ATG education or any services, statements, products or documents provided or associated therewith. ATG undertakes no obligation to update any of the forward-looking statements after the date of this press release.