Aspen Technology Announces Date of Second-Quarter 2006 Financial Results Release, Conference Call and Webcast

January 18, 2006

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Jan. 18, 2006--Aspen Technology, Inc. (Nasdaq: AZPN) a leading provider of software and services to the process industries, today announced that the company will disclose financial results for its fiscal 2006 second quarter, ended December 31, 2005, after the U.S. financial markets close on Tuesday, February 7, 2006.

In conjunction with this announcement, AspenTech will host a conference call and webcast on February 7, 2006, at 4:45 pm (EST) to discuss the Company's financial results, business outlook, and related corporate and financial matters. The live dial in number is: 1-877-239-3024, conference ID code: 4298806. Interested parties may also listen to a live webcast of the call by logging on to AspenTech's website: http://www.aspentech.com and clicking on the "webcast" link under the Investor Relations section of the site. A replay of the call will be archived on AspenTech's website and will also be available via telephone at: 1-800-642-1687 or 1-706-645-9291, conference ID code 4298806, for four days, beginning at 6:00 pm EST on February 7, 2006.

About AspenTech

Aspen Technology, Inc. provides industry-leading software and professional services that help process companies improve efficiency and profitability by enabling them to model, manage and control their operations. The new generation of integrated aspenONE (TM) solutions are aligned with the key industry business processes, providing manufacturers the capabilities they need to optimize operational performance, make real-time decisions and synchronize the plant and supply chain. Over 1,500 leading companies already rely on AspenTech's software, including Bayer, BASD, BP, Chevron Corporation, DuPont, ExxonMobil, Fluor, GlaxoSmithKline, Sanofi-Aventis, Shell and Total. For more information, visit www.aspentech.com.

AspenTech, aspenONE, HYSYS and the aspen leaf logo are trademarks of Aspen Technology, Inc., Cambridge, Mass.

CONTACT:
Aspen Technology, Inc.
Media:
Robin Swanger, 281-504-3256
robin.swanger@aspentech.com

Integrated Corporate Relations Investors:
Kori Doherty, 617-217-2084
kdoherty@icrinc.com