Exhibit 23.1

                         INDEPENDENT AUDITORS' CONSENT

    We consent to the incorporation by reference in this Registration Statement
on Form S-1 of ManTech International Corporation of our report dated November
16, 2001, except for Note 8, as to which the date is December 17, 2001,
appearing in the Registration Statement on Form S-1 No. 333-73946 of ManTech
International Corporation, and of our report dated November 16, 2001, relating
to the financial statement schedule appearing elsewhere in that Registration
Statement, all of which is incorporated by reference in this Registration
Statement.

    We also consent to the reference to us under the heading "Experts" in such
Registration Statement.

DELOITTE & TOUCHE LLP
McLean, Virginia
February 7, 2002

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