EXHIBIT 23.1


                   CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS



As independent public accountants, we hereby consent to the incorporation by
reference of our report dated April 12, 2001, included in this Form 10-K (which
contains an explanatory paragraph regarding CAIS Internet, Inc.'s ability to
continue as a going concern), into CAIS Internet, Inc.'s previously filed
Registration Statement File Nos. 333-91403, 333-31510 and 333-38332.


                                              ARTHUR ANDERSEN LLP


Vienna, Virginia
April 12, 2001