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                                                                   Exhibit 10.21
                                                                   -------------

                        ADDENDUM TO EMPLOYMENT AGREEMENT

      WHEREAS, Wyndham International, Inc. (the "Company") and Theodore Teng
(the "Executive") are parties to that certain Executive Employment Agreement
effective as of May 1, 2000 (the "Employment Agreement"); and

      WHEREAS, the Company and the Executive wish to amend certain provisions of
the Employment Agreement as specified in this Addendum to Employment Agreement
(this "Addendum");

      NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the Company and the Executive hereby agree that effective August
30, 2001, the Employment Agreement is amended as hereinafter set forth.

      1.    Certain Defined Terms. Capitalized terms not otherwise defined
            ---------------------
herein shall have the meanings ascribed to such terms in the Employment
Agreement.

      2.    Amendment to Paragraph 5. Unauthorized Disclosure. Paragraph 5 of
            -------------------------------------------------
the Employment Agreement is hereby deleted in its entirety and replaced with the
following:

            5.    Unauthorized Disclosure.
                  -----------------------

                  (a) Confidential Information. Executive acknowledges that in
                      ------------------------
            the course of his employment with the Company (and, if applicable,
            its predecessors), he has been allowed to become, and will continue
            to be allowed to become, acquainted with the business affairs,
            information, trade secrets, and other matters of the Company and its
            subsidiaries which are of a proprietary or confidential nature,
            including but not limited to the operations, business opportunities,
            price and cost information, finance, customer information, business
            plans, various sales techniques, manuals, letters, notebooks,
            procedures, reports, products, processes, services, and other
            confidential information and knowledge (collectively the
            "Confidential Information") concerning the business of the Company,
            its predecessors and their respective subsidiaries. The Company
            agrees to provide on an ongoing basis such Confidential Information
            as the Company deems necessary or desirable to aid Executive in the
            performance of his duties. Executive understands and acknowledges
            that such Confidential Information is confidential, and he agrees
            not to disclose such Confidential Information to anyone outside the
            Company except to the extent that (i) Executive deems such
            disclosure or use reasonably necessary or appropriate in connection
            with performing his duties on behalf of the Company, (ii) Executive
            is required by order of a court of competent jurisdiction (by
            subpoena or similar process) to

<PAGE>

            disclose or discuss any Confidential Information, provided that in
            such case, Executive shall promptly inform the Company of such
            event, shall cooperate with the Company in attempting to obtain a
            protective order or to otherwise restrict such disclosure, and shall
            only disclose Confidential Information to the minimum extent
            necessary to comply with any such court order; (iii) such
            Confidential Information becomes generally known to and available
            for use by the hotel and hospitality industry (the "Hotel
            Industry"), other than as a result of any action or inaction by
            Executive; or (iv) such information has been rightfully received by
            a member of the Hotel Industry or has been published in a form
            generally available to the Hotel Industry prior to the date
            Executive proposes to disclose or use such information. Executive
            further agrees that he will not during employment and/or at any time
            thereafter use such Confidential Information in competing, directly
            or indirectly, with the Company or any of its subsidiaries. At such
            time as Executive shall cease to be employed by the Company, he will
            immediately turn over to the Company all Confidential Information,
            including papers, documents, writings, electronically stored
            information, other property, and all copies of them provided to or
            created by him during the course of his employment with the Company.

                  (b) Heirs, successors, and legal representatives. The
                      --------------------------------------------
            foregoing provisions of this Paragraph 5 shall be binding upon
            Executive's heirs, successors, and legal representatives. The
            provisions of this Paragraph 5 shall survive the termination of this
            Agreement for any reason.

                  (c) Definition of Subsidiary. For purposes of this Paragraph 5
                      ------------------------
            and for purposes of Paragraph 6 (Covenant Not to Compete) below,
            "subsidiary" of the Company means any corporation, partnership,
            joint venture, limited liability company or other entity of which
            (i) at least a majority of the securities or other interests having
            by their terms voting power to elect a majority of the board of
            directors or others performing similar functions for such entity is
            directly or indirectly beneficially owned by the Company (either
            alone or through or together with one or more of its subsidiaries),
            or (ii) the Company or any subsidiary of the Company is a general
            partner or manager.

      3. Amendment to Paragraph 6. Covenant Not to Compete. Paragraph 6 of the
         -------------------------------------------------
Employment Agreement is hereby deleted in its entirety and replaced with the
following:

                  6. Covenant Not to Compete. In consideration for the Option,
                     -----------------------
            Stock Grant, loan evidenced by the Note, the Restricted Unit Award
            granted to Executive on April 12, 2001, the other consideration set
            forth in the Addendum, the Company's promise to provide Confidential
            Information as set forth in Paragraph 5 above (including the
            Confidential Information provided by the Company to Executive
            concurrently with the execution of the Addendum, which Executive
            acknowledges has not been previously provided to Executive), and for
            Executive's employment by the


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            Company under the terms provided in this Agreement, and as a means
            to aid in the performance and enforcement of the terms of and
            preserve the rights of the Company pursuant to the Unauthorized
            Disclosure provisions of Paragraph 5, Executive agrees as follows:

                        (a) during the term of Executive's employment with the
                  Company and for a period of twenty-four (24) months
                  thereafter, regardless of the reason for termination of
                  employment (other than termination by the Company without
                  Cause), Executive will not, directly or indirectly, as an
                  owner, director, principal, agent, officer, employee, partner,
                  consultant, servant, or otherwise, carry on, operate, manage,
                  control, or become involved in any manner with any business,
                  operation, corporation, partnership, association, agency, or
                  other person or entity which is in the business of owning,
                  operating, managing or granting franchise rights with respect
                  to hotels, motels or other lodging facilities in any location
                  in which the Company, or any subsidiary or affiliate of the
                  Company, operates or has plans or has projected to operate any
                  facility during Executive's term of Employment including any
                  area within a 50 mile radius of such facility (any "Business
                  Area"); provided, however, that the foregoing shall not
                  prohibit Executive from owning up to one percent (1%) of the
                  outstanding stock of a publicly held company engaged in the
                  hospitality business. Notwithstanding the foregoing, after
                  Executive's employment with the Company has terminated, upon
                  receiving written permission by the Board, Executive shall be
                  permitted to engage in such activities with respect to any
                  other hotel, motel or lodging facility that shall be
                  determined in the sole discretion of the Board in good faith
                  to be immaterial to the operations of the Company, or any
                  subsidiary or affiliate of the Company, in the area or
                  territory in question.

                        (b) during the term of Executive's employment with the
                  Company and for a period of twenty-four (24) months
                  thereafter, regardless of the reason for termination of
                  employment (other than termination by the Company without
                  Cause) Executive will not, directly or indirectly, either for
                  himself or for any other business, operation, corporation,
                  partnership, association, agency, or other person or entity,
                  call upon, compete for, solicit, divert, or take away, or
                  attempt to divert or take away any of the current or
                  prospective customers (including, without limitation, any
                  hotel owner, lessor or lessee, asset manager, trustee or
                  consumer with whom the Company, or any subsidiary or affiliate
                  of the Company, (i) has an existing agreement or business
                  relationship; (ii) has had an agreement or business
                  relationship within the two-year period preceding the
                  Executive's last day of employment with the Company; or (iii)
                  has included as a prospect in its applicable


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                  pipeline) or vendors of the Company, or any subsidiary or
                  affiliate of the Company, in any Business Area.

                        (c) during the term of Executive's employment with the
                  Company and for a period of twenty-four (24) months
                  thereafter, regardless of the reason for termination of
                  employment (other than termination by the Company without
                  Cause), Executive will not directly or indirectly solicit or
                  induce any current or prospective employee of the Company, or
                  any subsidiary or affiliate of the Company (including, without
                  limitation, any current or prospective employee of the Company
                  within the six-month period preceding Executive's last day of
                  employment with the Company or within the 24-month period of
                  this covenant) to accept employment with Executive or with any
                  business, operation, corporation, partnership, association,
                  agency, or other person or entity with which Executive may be
                  associated, and Executive will not employ or cause any
                  business, operation, corporation, partnership, association,
                  agency, or other person or entity with which Executive may be
                  associated to employ any current or prospective employee of
                  the Company, or any subsidiary or affiliate of the Company,
                  without providing the Company with ten (10) days' prior
                  written notice of such proposed employment.

                        (d) Executive agrees and acknowledges that the
                  restrictions contained in this noncompetition covenant are
                  reasonable in scope of activity, duration and geographical
                  area and are necessary to protect the Company's business
                  interests and Confidential Information after the Effective
                  Date of this Agreement. If any provision of this
                  noncompetition covenant as applied to any party or to any
                  circumstance is adjudged by a court to be invalid or
                  unenforceable, the same will in no way affect any other
                  circumstance or the validity or enforceability of this
                  Agreement. If any such provision, or any part thereof, is held
                  to be unenforceable because of the duration of such provision
                  or the scope of activity or area covered thereby, the parties
                  agree that the court making such determination shall have the
                  power to reduce the duration and/or area and/or scope of
                  activity of such provision, and/or to delete specific words or
                  phrases, and in its reduced form, such provision shall then be
                  enforceable and shall be enforced. The parties agree and
                  acknowledge that the breach of this noncompetition covenant
                  will cause irreparable damage to the Company, and upon breach
                  of any provision of this noncompetition covenant, the Company
                  shall be entitled to injunctive relief, specific performance,
                  or other equitable relief; provided, however, that this shall
                  in no way limit any other


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                  remedies which the Company may have (including, without
                  limitation, the right to seek monetary damages).

                        (e) Should Executive violate the provisions of this
                  Paragraph, then in addition to all other rights and remedies
                  available to the Company at law or in equity, the duration of
                  this covenant shall automatically be extended for the period
                  of time from which Executive began such violation until he
                  permanently ceases such violation.

      4. Amendment to Subparagraph (7)(e). Termination by Executive. The last
         ----------------------------------------------------------
two sentences of Subparagraph 7(e) of the Employment Agreement are hereby
deleted in their entirety and replaced with the following:

                  "Good Reason Process" shall mean that (i) the Executive
            reasonably determines in good faith that a "Good Reason" event has
            occurred; (ii) Executive notifies the Company in writing (the "Good
            Reason Notice") of the occurrence of the Good Reason event; (iii)
            for a period (the "Good Reason Process Period") consisting of (x)
            not less than thirty (30) days if the Good Reason Notice is
            delivered to the Company within 18 months after the occurrence of
            the first event constituting a Change in Control (as defined in
            Subparagraph 9(c)) or if the Good Reason event is an event specified
            in clause (C) of this Subparagraph 7(e) and (y) not less than ninety
            (90) days in all other instances, Executive cooperates in good faith
            with the Company's efforts to modify Executive's employment
            situation in a manner acceptable to Executive and the Company; and
            (iv) notwithstanding such efforts, one or more of the Good Reason
            events continues to exist and has not been modified in a manner
            acceptable to Executive. If the Company cures the Good Reason event
            during the applicable Good Reason Process Period, Good Reason shall
            be deemed not to have occurred.

      5. Amendments to Subparagraph 8(d)(i). The second sentence of Subparagraph
         ----------------------------------
8(d) is hereby deleted in its entirety and replaced with the following:

            In addition, subject to signing by Executive of a general release of
            claims in a form and manner satisfactory to the Company,

                  (i) the Company shall continue Executive's compensation of a
                  rate equal to the sum of Executive's Average Base Salary and
                  his Average Incentive Compensation payable for the remaining
                  length of the Period of Employment after the Date of
                  Termination, but in no event for fewer than twenty-four (24)
                  months (the "Severance Amount").

            The seventh complete sentence of Subparagraph 8(d)(i) of the
Employment Agreement is hereby deleted in its entirety and replaced with the
following:


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<PAGE>

            Notwithstanding the foregoing, in the event Executive terminates his
            employment for Good Reason as provided in Subparagraph 7(e), he
            shall be entitled to the Severance Amount only if he provides the
            Notice of Termination provided for in Subparagraph 7(f) within five
            (5) days after the expiration of the applicable Good Reason Process
            Period.

            Subparagraph 8(d)(ii) remains unchanged as provided in the
Employment Agreement.

      6. Amendment to Paragraph 9. Change in Control Payment. In the last
         ---------------------------------------------------
sentence of the first paragraph of Paragraph 9, the words "These provisions" are
hereby deleted and replaced with "The provisions of Subparagraph 9(a)".

      7. Amendments to Subparagraph 9(a). Change in Control. The first sentence
         --------------------------------------------------
of Subparagraph 9(a)(i) of the Employment Agreement is hereby deleted in its
entirety and replaced with the following:

            If within eighteen (18) months after the occurrence of the first
            event constituting a Change in Control, Executive's employment is
            terminated by the Company without Cause as provided in Subparagraph
            7(d) or Executive terminates his employment for Good Reason as
            provided in Subparagraph 7(e), then the Company shall pay Executive
            the Severance Amount as provided in Subparagraph 8(d)(i) in
            substantially equal bi-weekly installments, in arrears, over
            twenty-four (24) months; provided, however, that in the event
            Executive commences any employment with an employer other than the
            Company during such twenty-four (24) month period, the Company shall
            not be entitled to any right of set-off against the Severance Amount
            for any cash compensation received by the Executive from the new
            employer during such period.

            The following subparagraph is hereby inserted immediately following
Subparagraph 9(a)(iv):

            (v)   Notwithstanding Subparagraph 9(a)(iii), the Restricted Unit
                  Award granted to Executive on April 12, 2001 shall not vest as
                  provided in such Subparagraph 9(a)(iii) and shall instead vest
                  in accordance with the terms of such Restricted Unit Award.

      8. Amendments to Subparagraph 9(b). Gross Up Payment. Subparagraph 9(b)(i)
         -------------------------------------------------
of the Employment Agreement is hereby deleted in its entirety and replaced with
the following:

                  (i) Excess Parachute Payment. If Executive incurs the tax (the
            "Excise Tax") imposed by Section 4999 of the Internal Revenue Code
            of 1986 (the "Code") on "excess parachute payments" within the
            meaning of Section 280G(b)(1) of the Code, the Company will pay to
            Executive an amount such that the net amount retained by Executive,
            after deduction of any Excise Tax on the excess parachute payment
            and any federal, state and local income taxes and employment taxes
            (together with penalties and interest) and Excise Tax upon the
            payment provided for by this sentence, will be equal to the
            Severance Amount. In addition, if pursuant to the immediately
            preceding sentence a full gross up payment is not made to Executive
            for the entire amount of Excise Tax (and any federal, state and
            local income taxes and employment taxes (together with penalties and


                                       6

<PAGE>

            interest) and Excise Tax on the payment provided for in the
            immediately preceding sentence) incurred by Executive in connection
            with the first event constituting a Change in Control, then the
            Company will pay to Executive an additional amount that, after
            taking into account the amount payable pursuant to the immediately
            preceding sentence, will completely gross up the Executive for the
            entire amount of Excise Tax (and for any federal, state and local
            income taxes and employment taxes (together with penalties and
            interest) and Excise Tax on the payments provided for by this
            Subparagraph 9(b)(i)); provided, however, that any payment made
            pursuant to this sentence will not exceed an amount equal to twice
            the Executive's Base Salary or Adjusted Base Salary, as applicable,
            in effect immediately prior to the date of the Change in Control.
            The payments made pursuant to this Subparagraph 9(b)(i) are
            collectively referred to herein as the "Gross Up Payments". It is
            the intent that the Gross Up Payments provided for by this
            Subparagraph 9(b)(i) place Executive in the same position Executive
            would have been in had no Excise Tax been imposed, subject to the
            limitation on the Gross Up Payment provided for in the second
            sentence of this Subparagraph 9(b)(i) by the proviso of such
            sentence.

            Subparagraph 9(b)(ii) is hereby deleted in its entirety and replaced
with the following:

                  (ii) Applicable Rates. For purposes of determining the amount
            of the Gross Up Payments, Executive will be deemed to pay federal
            income taxes at the highest marginal rate of federal income taxation
            in the calendar year in which the Gross Up Payments are to be made
            and state and local income taxes at the highest marginal rates of
            taxation in the state and locality of Executive's primary residence
            for the calendar year in which the Gross Up Payments are to be made,
            net of the maximum reduction in federal income taxes that could be
            obtained from deduction of such state and local taxes.

            Subparagraphs 9(b)(iii) and 9(b)(iv) are hereby deleted in their
entirety and are replaced with the following:

                  (iii) Time for Payment. The Company will pay the estimated
            amount of the Gross Up Payments in cash to Executive at such time or
            times when the Excise Tax is due. Executive and the Company and
            their respective tax advisors agree to confer and reasonably
            cooperate in the determination of the actual amount of the Gross Up
            Payments. Without limiting the foregoing, Executive shall, if
            requested by the Company, cooperate in a valuation of Executive's
            obligations under paragraph 6 of


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            this Agreement by a valuation firm selected and paid for by the
            Company. Further, Executive and the Company agree to make such
            adjustments to the estimated amount of the Gross Up Payments as may
            be necessary to equal the actual amount of the Gross Up Payments,
            which in the case of Executive will refer to refunds of prior
            overpayments and in the case of the Company will refer to makeup of
            prior underpayments.

      9. Amendment to Subparagraph 9(c). Definitions. The penultimate sentence
         -------------------------------------------
of Subparagraph 9(c) is hereby deleted in its entirety and replaced with the
following:

            All defined terms used in the definition of "Change in Control"
            shall have the same meaning as set forth in the Certificate of
            Designation of Series B Convertible Preferred Stock of Wyndham
            International, Inc. as in effect on the Effective Date of this
            Agreement.

      10. Amendment to Paragraph 14. Arbitration; Other Disputes. Paragraph 14
          ------------------------------------------------------
of the Employment Agreement is hereby deleted in its entirety and replaced with
the following:

            14. Mediation and/or Arbitration; Other Disputes.
                --------------------------------------------

                  (a) General Procedures. In the event of any dispute or
                      ------------------
            controversy arising under or in connection with the terms of this
            Agreement, the parties shall first promptly try in good faith to
            settle such dispute or controversy by mediation under the Commercial
            Mediation Rules of the American Arbitration Association ("AAA")
            before resorting to arbitration, provided, however, that if the
            dispute or controversy concerns whether Executive is entitled to a
            payment under subparagraph 9(a) or 9(b) or the amount of any payment
            to which the Executive is entitled under subparagraph 9(a) or 9(b),
            the expedited procedures in subparagraph 14(b) will apply. In the
            event such dispute or controversy remains unresolved in whole or in
            part for a period of thirty (30) days after it is submitted to
            mediation, the parties will settle any remaining dispute or
            controversy exclusively by arbitration in Dallas, Texas in
            accordance with the Commercial Arbitration Rules of the AAA then in
            effect. The parties hereto agree that any dispute relating to the
            terms of this Agreement or the performance by the parties of their
            respective obligations under the terms of this Agreement shall not
            in any event be subject to the AAA's National Rules for the
            Resolution of Employment Disputes. Judgment may be entered on the
            arbitrator's award in any court having jurisdiction. With respect to
            a dispute or other controversy arising under or in connection with
            the terms of this Agreement after a Change in Control, all
            administration fees and arbitration fees shall be paid solely by the
            Company. Each party agrees to pay its own legal fees and expenses
            incurred in connection with mediation and/or arbitration.

                  Notwithstanding the above, the Company shall be entitled to
            seek a restraining order or injunction in any court of competent


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<PAGE>

            jurisdiction to prevent any continuation of any violation of
            paragraph 5 or 6 hereof. Should a dispute occur concerning
            Executive's mental or physical capacity as described in
            subparagraphs 7(b), 7(c) or 8(b), a doctor selected by Executive and
            a doctor selected by the Company shall be entitled to examine
            Executive. If the opinion of the Company's doctor and Executive's
            doctor conflict, the Company's doctor and Executive's doctor shall
            together agree upon a third doctor, whose opinion shall be binding.

                        Any amount to which Executive is entitled
            under this Agreement (including any disputed amount) which is not
            paid when due shall bear interest from the date due until paid at a
            rate equal to the lesser of eighteen percent (18%) per annum or the
            maximum lawful rate.

                  (b) Expedited Procedures. The following expedited procedures
                      --------------------
            apply in the event of any dispute or controversy concerning whether
            Executive is entitled to a payment under subparagraph 9(a) or 9(b)
            or the amount of any payment to which Executive is entitled under
            subparagraph 9(a) or 9(b), and are intended to supplement the
            general procedures detailed above. The parties shall first promptly
            try in good faith to settle such dispute or controversy by expedited
            mediation under the Commercial Mediation Rules of the AAA, as
            modified by this Agreement, before resorting to arbitration. In the
            event that such dispute or controversy remains unresolved in whole
            or in part for a period of fifteen (15) days after either party
            files a request for expedited mediation with the AAA, the parties
            will settle any remaining dispute or controversy exclusively by
            expedited arbitration in Dallas, Texas in accordance with the
            Expedited Procedures of the Commercial Arbitration Rules of the AAA
            then in effect, as modified by this Agreement. The parties agree
            that the arbitration hearing will be held sixty (60) days after the
            filing of a demand for expedited arbitration. The parties further
            agree that the following deadlines shall apply: (1) a party has
            fifteen (15) days following the conclusion of the mediation period
            to file an arbitration demand; (2) the opposing party then has seven
            (7) days to file an answering statement; (3) thereafter, the parties
            have thirty-five (35) days to conduct discovery, and (4) the parties
            have seven (7) days following the close of discovery to exchange
            copies of all exhibits that they intend to submit at the hearing.
            During the first five (5) days of the discovery period, and prior to
            either party starting discovery, the parties must agree upon the
            type of discovery that will be conducted and upon a discovery
            schedule. Any dispute regarding the type of discovery or the
            discovery schedule must be resolved by the arbitrator during a
            discovery conference conducted in person or on the telephone within
            the first five (5) days of the discovery period. The parties agree
            that the arbitrator shall have fifteen (15) days after the
            arbitration hearing to issue an award. The award shall be written
            and reasoned, if requested by one of the parties.


                                       9

<PAGE>

      11. Governing Law. The validity, interpretation, construction, and
          -------------
performance of this Addendum shall be governed by the laws of the State of Texas
(without regard to principles of conflicts of laws).

      12. Counterparts. This Addendum may be executed in several counterparts,
          ------------
each of which shall be deemed an original but all of which together will
constitute one and the same instrument.


                                       10

<PAGE>

      IN WITNESS WHEREOF, the parties hereto have executed this Addendum
effective as of August 30, 2001.

                           WYNDHAM INTERNATIONAL, INC.


                           By:/s/ Mary E. Watson
                              --------------------------------------------------
                           Name:  Mary E. Watson
                                ------------------------------------------------
                           Title: Senior Vice President - Human Resources
                                 -----------------------------------------------

                           /s/ Theodore Teng
                           -----------------------------------------------------
                           Theodore Teng, Executive


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