1 EXHIBIT 21.1 PROJECT SOFTWARE & DEVELOPMENT, INC. List of Subsidiaries Name of Subsidiary Jurisdiction of Ownership - ------------------ --------------- --------- Incorporation ------------- PSDI International Software, Inc. Delaware (1) PSDI Security Corporation Massachusetts (1) Maintenance Automation Corporation Florida (1) PSDI International Holdings Inc. Delaware (2) PSDI Export, Inc. Barbados (2) PSDI (UK) Ltd. United Kingdom (2) PSDI Canada Limited Canada (2) PSDI France SARL France (2) PSDI Australia PTY. Ltd. Australia (2) PSDI Deutschland GmbH Germany (2) PSDI Europe, Ltd United Kingdom (2) PSDI Espana S.A. Spain (2) PSDI Benelux N.V. Netherlands (2) PSDI Norden AB Sweden (2) PSDI Japan K.K. Japan (2) PSDI (Thailand) Limited Thailand (2) PSDI India India (2) PSDI Brasil Ltda. Brazil (3) (1) All of the outstanding capital stock is owned by Project Software & Development, Inc. (2) All of the outstanding capital stock (other than certain qualifying shares required in the jurisdiction of organization and representing from 0% to 2% of the outstanding capital stock), is owned by PSDI International Software, Inc. (3) 4,950 shares are owned by PSDI International Software, Inc. and 50 shares are owned by PSDI International Holdings, Inc.