Exhibit 21.1

SUBSIDIARIES OF REGISTRANT AT DECEMBER 31, 2000


The companies listed below are directly or indirectly owned 100% by GSE Systems,
Inc. and are included in its consolidated financial statements.

     GS Information  Systems FSC, Ltd., GSE Systems  International  Ltd.,  MSHI,
Inc., GSE Power Systems AB, GSE Process  Solutions,  Inc., GSE Erudite Software,
Inc., and VirtualPlant, Inc. are wholly owned subsidiaries of GSE Systems, Inc.

     GP  International  Engineering & Simulation,  Inc. and GSE Services Company
L.L.C.  are wholly owned  subsidiaries  of GSE Power  Systems,  Inc.  which is a
wholly owned subsidiary of MSHI, Inc.

     GSE Systems  UK,  Ltd.  and GSE Process  Solutions  B.V.  are wholly  owned
subsidiaries of GSE Process Solutions, Inc.

     GSE Process Solutions Singapore (Pte) Limited is a wholly owned subsidiary
of GSE Process Solutions B.V.

     J.L. Ryan, Inc., acquired by GSE Power Systems,  Inc. in December 1997, has
been merged with and into GSE Power Systems,  Inc. as of February 1998, with GSE
Power Systems, Inc. being the surviving corporation.

Name                                     Place of Incorporation or Organization

GS Information Systems FSC, Ltd.                      Barbados
GSE Systems International Ltd.                        State of Delaware
MSHI, Inc.                                            State of Virginia
GSE Power Systems AB                                  Sweden
GSE Process Solutions, Inc.                           State of Delaware
GSE Erudite Software, Inc.                            State of Delaware
VirtualPlant, Inc.                                    State of Delaware
GP International Engineering                          State of Delaware
    & Simulation, Inc
GSE Services Company L.L.C.                           State of Delaware
GSE Power Systems, Inc.                               State of Delaware
GSE Systems UK, Ltd.                                  United Kingdom
GSE Process Solutions B.V.                            Netherlands
GSE Process Solutions Singapore                       Singapore
    (Pte) Limited