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                                 EXHIBIT 10.18

                         AMENDMENT TO LEASE AGREEMENT

That certain Commercial Lease Agreement dated April 6, 1998 between JACKSON-SHAW
TECHNOLOGY CENTER II, LTD., (LANDLORD) and ADAMS GOLF, INC., (TENANT), for
approximately 32,996 square feet of office/flex space located at 2805 E. Plano
Parkway, Plano, Texas, is hereby amended as follows:

Whereas Adams Golf, Inc. is desirous of terminating its obligations on 12,031
square feet of the total 32,996 square feet under said Commercial Lease
Agreement.

LEASED PREMISES: The size of the Leased Premises as described in paragraph 3 of
that certain Commercial Lease Agreement shall be modified and amended as
follows:

   1)    In consideration of the rents, terms and covenants of the Commercial
         Lease Agreement (this "Lease), Landlord hereby leases to Tenant certain
         premises (the "Leased Premises") consisting of approximately 20,965
         square feet within the 67,372 square foot building (the "Building")
         located at 2805 E. Plano Parkway, Plano, Texas, together with the
         non-exclusive right to use, in common with other tenants, the common
         areas of the Project, which are all areas neither exclusively leased to
         another tenant or expressly reserved to or by Landlord. The Land upon
         which the building, landscaping, parking and driveway areas, sidewalks,
         and other improvements thereon, shall be referred to in this Lease as
         the "Project."

TERM: The term of this Lease referenced above and as described in paragraph 4(a)
and (d) shall be modified and amended as follows:

   1)    The term of this Lease shall be 50 months commencing on February 1,
         2000, the "Commencement Date" and terminating on March 31, 2004,
         the "Termination Date."

BASE RENT AND SECURITY DEPOSIT: Base Rent as described in Paragraph 5(a) of
the Lease Agreement shall be modified and amended as follows:

   1)    Tenant agrees to pay to Landlord the following rental amounts
         (sometimes referred to in this lease as the "Base Rent" or "Base
         Rental"): months 1 through 4 $146,760.00 per year payable in monthly
         installments of $12,230.00 each; months 5 through 27, $154,476.00 per
         year payable in monthly installments of $12,873.00 each; months 28
         through 50, $167,736.00 per year payable in monthly installments of
         $13,978.00 each. Payment of rent is subject to proration for partial
         months and to adjustment for early or delayed occupancy under the terms
         hereof, and, if the area of the Leased Premises is, on the Commencement
         Date, different than the area stated in paragraph 3 of the Lease
         Agreement, then Base Rent shall be adjusted to reflect the then current
         rent. Upon the date Tenant executes the Lease Agreement the first
         months Base Rent shall be payable. All subsequent payments shall be
         made to Landlord monthly, in advance, without demand, deduction or
         offset, in lawful money of the United States of America at the address
         stated in the Lease Agreement. All installments of Base Rent shall be
         due and payable on or before the first (1st) day of each month during
         the Lease term. Notwithstanding anything contained herein to the
         contrary, Tenant represents and warrants that the Premises and meet and
         comply with all federal, state, and local laws, ordinances and
         regulations (including but not limited to all accessibility
         requirements) and are in good sanitary order, condition, and repair at
         delivery of the premises to Landlord. Upon termination of this Lease
         Agreement, Tenant shall perform, at no cost to Landlord, the following:
         (a) separation of utilities, including HVAC and electrical service
         (which electrical service shall be sub-metered at no cost to Landlord;
         (b) removal of the server system presently located in the Premises; (c)
         seal and paint current opening in the demising wall; and (d) obtain a
         final approved building inspection of such work.

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HAZARDOUS WASTE: Hazardous Waste as described in paragraph 38 of the Lease
Agreement shall be modified and amended as follows:

         Tenant warrants, represents, covenants and agrees (1) to the best of
         Tenant's knowledge, Tenant has not used, generated, manufactured,
         produced, stored, released, discharged or disposed of on, under, about
         the Premises (or off site of the Premises that might affect the
         Premises) or transferred to or from the Premises, any Hazardous
         Substance or allowed any other person or entity to do so. Tenant has
         no knowledge or reason to know that any Hazardous Substance has been
         used, generated, manufactured, produced, stored, released, discharged
         or disposed of on, under or about the Premises or the Development (or
         off site of the Development that might affect the Premises) or
         transported to or from the premises or the Development (or off site of
         the Development that might affect the Premises) or transported to or
         from the premises or the Development (or off site of the Development
         that might affect the Premises) by any entity, firm or person, or from
         any source whatsoever.

MISCELLANEOUS: Miscellaneous items as outlined in Paragraph 42 of the Lease
Agreement shall be modified and amended as follows:

   1)    Tenant agrees to assign to Nextlink Communications approximately 95 of
         the 115 parking spaces available currently to Adams Golf.

ALL OTHER TERMS, CONDITIONS, AND PROVISIONS OF THE LEASE AGREEMENT SHALL
REMAIN UNMODIFIED.

AGREED TO AND ACCEPTED ON THIS 31 DAY IN JANUARY 2000 BY:

LANDLORD                                TENANT:
JACKSON-SHAW TECHNOLOGY                 ADAMS GOLF, INC.
CENTER II, LTD.

BY: JACKSON-SHAW/TEXAS, INC.
       GENERAL PARTNER

/s/ Stephen S. Kurth                    /s/ Richard Murtland
----------------------------            ----------------------------
BY: STEPHEN S. KURTH                    BY: RICHARD MURTLAND
ITS: FIRST VICE PRESIDENT               ITS: VICE PRESIDENT OF OPERATIONS<PAGE>
                                                             EXHIBIT 4.1
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===================================================================================================================================

                                                            [CERTIFICATE]

                                                     INCORPORATED UNDER THE LAWS
                                                       OF THE STATE OF DELAWARE

              NUMBER                                                                                           SHARES
        CA                                               UNITEDGLOBALCOM, INC.

       CLASS A COMMON STOCK                                                                               CUSIP 913247 50 8

THIS CERTIFICATE IS TRANSFERABLE IN
NEW YORK, NY AND RIDGEFIELD PARK, NJ                                                            SEE REVERSE FOR CERTAIN DEFINITIONS
        ------------------------------------------------------------------------------------------------------------------

              THIS CERTIFIES that

              is the owner of
        ------------------------------------------------------------------------------------------------------------------

                       FULLY PAID AND NON-ASSESSABLE SHARES OF THE CLASS A COMMON STOCK, $.01 PAR VALUE, OF
                                                         UNITEDGLOBALCOM, INC.
        transferable on the books of the Corporation by the holder hereof, in person or by duly authorized attorney, upon
        surrender of this Certificate properly endorsed. This Certificate is not valid unless countersigned by the Transfer
        Agent and registered by the Registrar.
              WITNESS the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers.

                               /s/ Gene Schneider                     Dated:

                             CHIEF EXECUTIVE OFFICER                  COUNTERSIGNED AND REGISTERED:
                                                                               CHASEMELLON SHAREHOLDER SERVICE, L.L.C.
                                                                                              TRANSFER AGENT AND REGISTRAR
                                                          [SEAL]

                              /s/ Ellen Spangler                      BY

                                   SECRETARY                                                          AUTHORIZED SIGNATURE

===================================================================================================================================
                                                AMERICAN BANK NOTE COMPANY
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                              UNITEDGLOBALCOM, INC.

     The Corporation will furnish without charge to each shareholder who so
requests a full statement of the designations, preferences, limitations and
relative rights of each class of stock or series thereof of the Corporation
and the variations in the relative rights and preferences between the shares
of any series of preferred stock, so far as the same have been fixed and
determined, and the authority of the board of directors to fix and determine
the relative rights and preferences of any series of preferred stock. Such
requests may be made to the Corporation or to the transfer agent.

                                 ABBREVIATIONS

     The following abbreviations, when used in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

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     TEN COM -- as tenants in common               UNIF GIFT MIN ACT--_______________Custodian_______________
     TEN ENT -- as tenants by the entireties                               (Cust)                  (Minor)
     JT TEN  -- as joint tenants with right of                               under Uniform Gifts to Minors
                survivorship and not as tenants                        Act____________________________________
                in common                                                             (State)
</TABLE>

      Additional abbreviations may also be used though not in the above list.

FOR VALUE RECEIVED, __________________________________ hereby sell, assign and
transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE
--------------------------------------

--------------------------------------

--------------------------------------------------------------------------------
 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------Shares
of the Class A Common Stock represented by the within Certificate, and do hereby
irrevocably constitute and appoint

------------------------------------------------------------------------Attorney
to transfer the said Shares on the books of the within named Corporation with
full power of substitution in the premises.

Dated _________________________

                                  Signature(s):

                                  X ____________________________________________

                                  X ____________________________________________
                            NOTICE: THE SIGNATURE OF THIS ASSIGNMENT MUST
                                    CORRESPOND WITH THE NAME AS WRITTEN UPON THE
                                    FACE OF THE CERTIFICATE IN EVERY PARTICULAR,
                                    WITHOUT ALTERATION OR ENLARGEMENT OR ANY
                                    CHANGE WHATEVER.

Signature(s) Guaranteed

By _____________________________________________
THE SIGNATURE(S) MUST BE GUARANTEED BY AN
ELIGIBLE GUARANTOR INSTITUTION (BANKS,
STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND
CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED
SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT
TO S.E.C. RULE 17Ad-15.

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