<PAGE>
 
                                 VISTANA, INC.
                           8801 VISTANA CENTRE DRIVE
                            ORLANDO, FLORIDA 32821

                                 March 4, 1999


Mr. Mark E. Patten
Vice President & Chief Accounting Officer
Vistana, Inc.

     Re: First Amendment to Employment Agreement
         ---------------------------------------

Dear Mark:

     Attached hereto is a revised Schedule B to the Employment Agreement dated 
January 30, 1998 between Vistana, Inc. and you which incorporates the adjustment
to your Base Salary and Annual Bonus Amount for the 1999 fiscal year approved by
the Compensation Committee at its February meeting.

     Please carefully review the enclosed Schedule B to confirm the accuracy 
thereof. If the enclosed Schedule B is accurate, please execute the enclosed 
copy of this letter in the space provided below and return it to the 
undersigned, whereupon the enclosed Schedule B will be substituted for the 
existing Schedule B. Please keep your copy of this letter and revised Schedule
B with your own copy of your Employment Agreement.


                                            Very truly yours,

                                            VISTANA, INC.


                                            By:  /s/ Jeffrey A. Adler
                                               ---------------------
                                               Name: Jeffrey A. Adler
                                               Title: President


Enclosure

ACKNOWLEDGED AND CONFIRMED:

/s/   Mark E. Patten
--------------------------
Name: Mark E. Patten
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                                  SCHEDULE B

                                      to

                   EMPLOYMENT AGREEMENT with MARK E. PATTEN
                     (Revised Effective January 30, 1999)


1.   Base Salary: For the remainder of the 1999 calendar year, the Company shall
     pay to Employee an annual salary equal to $177,500 (the "Base Salary"). For
     each calendar year during the term of this Agreement commencing with the
     next ensuing calendar year, the Company shall pay Employee an annual salary
     (the "Adjusted Base Salary") determined by the Company's Chief Executive
     Officer or its Board of Directors (or the Compensation Committee thereof);
     provided, however, that the Adjusted Base Salary shall be no less than the
     Base Salary.


2.   Bonus Amount: From and after January 1, 1999, Employee shall be entitled to
     annual bonuses, if any, as shall be specified in written performance plans
     which are agreed to by the Company and Employee on a year-to-year basis.
     The Company and Employee acknowledge that (i) such performance plans shall
     be similar in form to that currently in effect for similar level employees
     of the Company having responsibilities similar to the responsibilities of
     Employee hereunder and (ii) such performance plans shall provide
     eligibility for annual bonuses not to exceed 30% of Employee's Base Salary
     or Adjusted Base Salary (as applicable).


3.   Paid Vacation Time: Four weeks per calendar year. (Unused vacation time may
     not be carried over from year to year unless approved by the Company in
     writing or permitted by Company policy).


4.   Severance Amount: Employee's monthly Base Salary (or, if applicable,
     Adjusted Base Salary) payable (in accordance with the Company's normal
     payroll policies) during the Severance period.


5.   Severance Period: The period from the Termination Date until the earlier to
     occur of (i) the twelve months' anniversary of the Termination Date and
     (ii) the Expiration Date.

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