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EXHIBIT 23.3
CONSENT OF INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3, No. 333-_____) and related Prospectus of
USinternetworking, Inc. for the registration of up to $150,000,000 of its common
stock, and to the incorporation by reference therein of our report dated March
23, 1999, with respect to the consolidated financial statements of I.I.T.
Holding, Inc. and subsidiaries included in the Annual Report (Form 10-K) of
USinternetworking, Inc. for the year ended December 31, 1999, filed with the
Securities and Exchange Commission.
/s/ Ernst & Young LLP
Baltimore, Maryland
October 11, 2000
