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Exhibit 23.1
INDEPENDENT AUDITORS' CONSENT
We consent to the incorporation by reference in this Registration Statement of
OPNET Technologies, Inc. on Form S-8 of our report dated April 19, 2000, except
for note 15 paragraph 1, paragraph 2, paragraphs 3 through 5, and paragraph 6 as
to which the dates are June 2, 2000, June 5, 2000, June 10, 2000, and June 27,
2000 respectively, contained in Registration Statement No. 333-32588 of OPNET
Technologies, Inc. on Form S-1 under the Securities Act of 1933 insofar as such
report relates to the financial statements of OPNET Technologies, Inc. for the
year ended March 31, 2000.
DELOITTE & TOUCHE LLP
McLean, Virginia
August 23, 2000
