[Letterhead of Gray Plant Mooty Mooty & Bennett, P.A.]

                                                                     Exhibit 5.1


                                                   Lindley S. Branson
                                                   612 343-2827

                                  May 25, 2001

Webb Interactive Services, Inc.
1899 Wynkoop
Suite 600
Denver, CO 80202

     RE:  Form S-3 Registration Statement

Ladies and Gentlemen:

     This opinion is furnished in connection with the registration, pursuant to
the Securities Act of 1933, as amended, of a maximum of 3,966,979 shares of
common stock, no par value (the "Shares"), of Webb Interactive Services, Inc.
("Webb"), including 504,136 shares (the "Shares") currently outstanding and up
to 3,367,974 shares issuable upon the conversion of Webb's 10% Convertible
Promissory Note and similar notes issued in payment of interest on the note,
Series B-2 Convertible Preferred Stock and Series C-1 Convertible Preferred
Stock and the exercise of Webb's stock purchase warrants issued in connection
with Webb's Series B Convertible Preferred Stock, 10% Promissory Notes and
Series C-1 Convertible Preferred Stock (the Promissory Notes, Preferred Stock
and Warrants being referred to herein as the "Derivative Securities" and the
common stock subject to the Derivative Securities being referred to herein as
the "Derivative Shares").

     We have acted as counsel to Webb in connection with the preparation of the
Form S-3 Registration Statement (the "Registration Statement"). We have examined
the Articles of Incorporation, as amended, the Bylaws of the Company, such
records of proceedings of Webb as we deemed material and such other
certificates, records and documents as we considered necessary for the purposes
of this opinion.

     Based on the foregoing, we are of the opinion that the Shares and the
Derivative Shares when issued in accordance with the terms of the Derivative
Securities will be legally issued, fully paid and non-assessable securities of
Webb. We understand that this opinion is to be issued in connection with the
Registration Statement. We consent to a filing of a copy of this opinion with
the Registration Statement. We also consent to the reference to us under the
heading "Legal Matters" in the Registration Statement.

                                           Very truly yours,


                                           GRAY, PLANT, MOOTY,
                                            MOOTY & BENNETT, P.A.



                                        By /s/ Lindley S. Branson
                                           -------------------------------------
                                           Lindley S. Branson