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

April 18, 2006

CAMBRIDGE, Mass.--(BUSINESS WIRE)--April 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 third quarter, ended March 31, 2006, after the U.S. financial markets close on Tuesday, May 9, 2006.

In conjunction with this announcement, AspenTech will host a conference call and webcast on May 9, 2006, at 4:45 pm EDT 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 7899945. Interested parties may also listen to a live webcast of the call by logging on to the Investor Relations section of AspenTech's website, http://www.aspentech.com/corporate/investor.cfm, and clicking on the "webcast" link. 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 7899945, through May 16, 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, BASF, BP, Chevron Corporation, DuPont, ExxonMobil, Fluor, GlaxoSmithKline, Sanofi-Aventis, Shell and Total. For more information, visit www.aspentech.com.

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

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

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