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                                                                 Exhibit 10.17.1

                                   AMENDMENT 1

THIS AMENDMENT 1 ("Amendment 1") is made and entered into this 19 day February,
2002, by and between Williams Communications, LLC, a Delaware limited liability
company ("Williams") and Universal Access, Inc., a Delaware corporation
("Customer") having it's principal place of business at Sears Tower, 223 S.
Wacker, Suite 600, Chicago, Illinois 60606.

WHEREAS, Williams and Customer are parties to that certain Master Services
Agreement dated October 1, 2001, contract number 01R1966.00 (the "Agreement");

WHEREAS, Williams and Customer desire to amend the Agreement;

NOW, THEREFORE in consideration of the foregoing premises and mutual promises
and covenants of the parties hereto, the receipt and sufficiency of which is
hereby acknowledged, Williams and Customer agree to amend the Agreement as
follows:

1. Section 1.1, Table A is hereby amended to include Schedule 17, Managed
Services.

2. Section 2.3(c), of the Agreement is deleted in its entirety and replaced with
   the following:

   c. In determining whether the annual charges are of a sufficient dollar
   amount to meet Customer's Revenue Commitment, Williams will include the
   monthly recurring charges for Williams' Services. The monthly recurring
   charges for Williams Service(s) (including one month's charge for pending
   circuits prior to their delivery subject to the last sentence of the
   following paragraph), and any charges for any circuit or bandwidth ordered by
   Customer from Williams pursuant to any circuit or bandwidth trade, whether
   directly between the parties or through a broker, and whether any such trade
   is governed by a separate agreement between the parties, shall be considered
   an "Applicable Service". The term Applicable Service shall also include all
   charges and fees associated with any such circuit or bandwidth and any paid
   Deficiency Amounts, (as discounted, if applicable) and any credits to which
   Customer may be entitled pursuant to this Agreement as. well as any amounts
   paid by Customer pursuant to Section 3 of Schedule 17 for Managed Services.
   The foregoing not withstanding, the Applicable Services will not include late
   charges, non-recurring charges, ancillary charges, payment penalties, taxes
   and other government imposed surcharges, payments made by Customer for Third
   Party Services (including but not limited to Third Party Local Access
   Service), amounts paid for Equipment Sales and Travel Expenses associated
   with Managed Services as specified in Attachment 1 to Schedule 17, and
   amounts paid to reimburse Williams for costs paid by Williams to any Third
   Party Provider.

   To the extent that, in any year during the Term of this Agreement, Customer
   fails to have a total aggregate billing of Applicable Services from Williams
   greater than or equal to the Annual Minimum amount applicable to a year,
   Williams shall invoice Customer, on Customer's current or next invoice, and
   Customer hereby agrees to pay, an amount equal to the difference between the
   Annual Minimum amount and the amount of Applicable Services actually
   purchased by Customer (the "Deficiency Amount") for such year. The parties
   agree that the Deficiency Amount represents liquidated damages, and is based
   on Customer's commitment to meet the Annual Minimum amount during each year
   of the Term of this Agreement and Williams' agreement to the discounted
   prices set forth in the Service Schedules attached hereto, which are based
   upon such commitment. Notwithstanding the foregoing, in the event that
   Customer has not taken delivery of an Applicable Service within forty-five
   (45) days after the end of the immediately preceding year, then Williams
   shall not count the monthly recurring charges for Williams' Services as set
   forth in such Service Orders towards Customer's Annual Minimum.

3. Except as specifically amended herein, all the covenants, terms and
   conditions and provisions contained in the Agreement shall remain unchanged
   and in full force and effect.

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                                   AMENDMENT 1

IN WITNESS WHEREOF, the parties have executed this Amendment 1 on the day and
year first set forth above.

UNIVERSAL ACCESS, INC.                       WILLIAMS COMMUNICATIONS, LLC:
/s/ Brian Coderre                            /s/ Robert Traill
-----------------------------------          -----------------------------------
Signature of Authorized                      Signature of Authorized
Representative                               Representative
Brian Coderre                                Robert Traill
-----------------------------------          -----------------------------------
Printed Name                                 Printed Name
Senior VP Carrier Relations                  VP Strategic Sourcing
-----------------------------------          -----------------------------------
Title                                        Title
2-14-02                                      2-19-02
-----------------------------------          -----------------------------------
Date                                         Date

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