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                                                                 Exhibit 10.23.1

                     AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT


        Amendment No. 1 dated as of February 1, 2000 (the "Amendment") to the
Employment Agreement and any exhibits thereto (the "Agreement") by and between
Universal Access, Inc., a Delaware corporation (the "Company") and Donna Shore
(the "Employee"). Any capitalized terms not defined herein shall have the
meanings assigned to those terms in the Agreement.


                                    RECITALS

        A. Company and Employee entered into the Agreement on November 16, 1998.

        B. Company and Employee desire to amend the Agreement to reflect certain
changes agreed to by the Company and the Employee.

        NOW, THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth, and for other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, it is hereby agreed as
follows:

        1. All references in the Agreement to "Vice President of Finance" shall
be deleted and replaced by references to "Executive Vice President, Chief
Financial Officer and Treasurer".

        2. The figure of $125,000 in paragraph A (1) of Exhibit A to the
Agreement shall be deleted and replaced by the figure of $ 175,000.

        3. Section 6.3 of the Agreement is hereby deleted in its entirety and
replaced by the following:

               6.3 Entire Agreement; Amendments, Etc. This Agreement and the
            Indemnification Agreement dated as of January 7, 2000 between the
            Company and Employee (as the Indemnification Agreement may be
            amended, restated or otherwise modified) contain the entire
            agreement and understanding of the parties hereto, and supersede all
            prior agreements and understandings relating to the subject matter
            hereof and thereof. Except as provided in Section 4.4(b), no
            modification, amendment, waiver or alteration of this Agreement or
            any provision or term hereof shall in any event be effective unless
            the same shall be in writing, executed by both parties hereto, and
            any waiver so given shall be effective only in the specific instance
            and for the specific purpose for which given.

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        4. Miscellaneous. Upon the execution and delivery of this Amendment, the
Agreement shall be amended and supplemented as set forth herein, as fully and
with the same effect as if the amendments and supplements made hereby were set
forth in the Agreement as of the date hereof. This Amendment and the Agreement
shall henceforth be read, taken and construed as one and the same instrument,
but this Amendment shall not operate so as to render invalid or improper any
action previously taken under this Agreement.


        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of February 1, 2000.


               COMPANY:                     UNIVERSAL ACCESS, INC.,
                                            a Delaware corporation


                                            By:    /s/ PATRICK C. SHUTT
                                                   ------------------------
                                            Name:  Patrick C. Shutt
                                            Title:    President and CEO


               EMPLOYEE:                    By:    /s/ DONNA SHORE
                                                   ------------------------
                                                   Donna Shore