DSET Named "Hot Growth" Company by Business Week Magazine

Bridgewater, NJ - May 26, 2000 - (NASDAQ: DSET) - DSET Corporation, a leading supplier of business-to-business e-commerce connectivity solutions for the telecom industry, announced today that it has been named one of the nation's top 100 "hot growth" companies by Business Week magazine.

As explained in the May 29 issue of Business Week, winning a spot on this list of companies with $25 million to $500 million in annual sales requires outstanding performance in three areas - three-year results in sales growth, earnings growth, and return on invested capital. DSET has achieved more than 50% growth in sales and profits and over 16% return on capital for the three-year period.

"This recognition is another indicator of DSET's solid, dynamic presence in the competitive telecom market as the leader in operations support system interconnection software," said Bruce Crowell, DSET vice president and chief financial officer. "It also validates our strategy for achieving consistent, substantial growth in both revenues and profitability and maintaining a high return on capital in what is often a volatile business environment."

About DSET:

DSET Corporation is a leading provider of business-to-business e-commerce connectivity solutions for the global telecommunications marketplace. The DSET suite of electronic-bonding gateways is designed to interconnect the operations support systems (OSSs) of service providers that must exchange information and share network capabilities with trading partners to provision and maintain a growing range of services for customers in the competitive telecom market. DSET's local number portability solutions play a key role in enabling business and residential customers to change service providers without changing their local phone numbers. 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.

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DSET Contacts:

Media Relations: Dean Maskevich, Marketing Communications, 908-526-7500 Ext. 1366, e-mail: dmaskevi@dset.com

Investor Relations: John P. Murphy, Westfield Investor Relations, 908-233-1558, e-mail: westfieldir@worldnet.att.net

DSET and the DSET logo are registered trademarks of DSET Corporation.

All other trademarks are the property of their respective owners.