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                                                                  EXHIBIT 23.1


                       CONSENT OF INDEPENDENT AUDITORS




We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3, No. 333-55104) and related Prospectus of
USinternetworking, Inc. for the registration of 48,658,041 shares of common
stock, and to the incorporation by reference therein of our report dated
February 15, 2001, with respect to the consolidated financial statements of
USinternetworking, Inc. included in its Annual Report (Form 10-K) for the year
ended December 31, 2000, filed with the Securities and Exchange Commission.

                                /s/ Ernst & Young LLP




Baltimore, Maryland
April 16, 2001