DSET Will Report First-Quarter Results on April 26

Conference Call Also to Be Broadcast on the Internet

Bridgewater, NJ - April 20, 2001 - (Nasdaq: DSET) - DSET Corporation announced today that it will release first-quarter financial results on Thursday, April 26 after the close of trading for the day. A conference call will be held at 11:00 AM Eastern Time on April 27 during which the quarter's results will be discussed by William P. McHale, Jr., DSET's chairman, president and chief executive officer, and by Bruce M. Crowell, vice president and chief financial officer of DSET.

Investors can listen to a live Webcast of the conference call at www.StreetFusion.com. The DSET Web site, www.dset.com, will also have a direct link to the conference-call broadcast at this site. Listeners should go to the Web site at least 15 minutes prior to the call to download and install any necessary audio software.

For those who cannot listen to the live Webcast, the teleconference will be archived on both the DSET and StreetFusion sites for 30 days. In addition, you may also listen to the playback of the call after 2:30 PM by dialing 1-800-475-6701, access code 583386 through May 4, 2001.

About DSET

DSET is a leading supplier of software known as electronic-bonding gateways as well as services that enable competitive service providers in the telecommunications industry to implement automated Trading Partner Networks (TPNs). TPNs lower the cost of acquiring customers, reduce the amount of time required to turn on services for new customers, and minimize the time required to resolve service outages to ensure higher customer satisfaction and less customer turnover. DSET provides the installation, interoperability-testing, training, and maintenance services needed to put TPNs into production and maintain efficient operation. DSET is headquartered in Bridgewater, New Jersey, and the company's Web site can be viewed at www.dset.com.

Statements regarding financial matters contained in this press release, other than historical facts, are forward-looking. Since all statements about DSET's plans, estimates, and expectations are based on current projections that involve risks and uncertainties, and are subject to change at any time, the company's actual results may differ materially from expected results. Investors should consider these risks and uncertainties, which are discussed in documents filed by DSET with the Securities and Exchange Commission. These documents identify important factors that could cause the actual results to differ materially from those contained in the projections or forward-looking statements. DSET expressly disclaims any obligation to update any forward-looking statements.