<PAGE>   1

                         EXHIBIT 10 - MATERIAL CONTRACTS

                     FIRST AMENDMENT TO CONSULTING AGREEMENT

         This First Amendment to the Consulting Agreement is effective the first
day of February, 1999 (the "First Amendment"), by and between MICROS SYSTEMS,
INC., a Maryland corporation, with offices located at 12000 Baltimore Avenue,
Beltsville, Maryland 20705 (hereinafter referred to as the "Company"), and Louis
M. Brown, Jr., whose address is 1665 Kenwood Avenue, Alexandria, Virginia 22312
(hereinafter referred to as the "Consultant").

         WHEREAS, the Consultant and the Company entered into a Consulting
Agreement dated June 30, 1995 (the "Agreement"); and

         WHEREAS, the parties hereto would like to amend the Agreement pursuant
to this First Amendment in an effort: (i) to reflect the rapid growth
experienced by the Company, and the current status of the Company and the
Consultant relative to other similarly positioned entities; (ii) to reward the
Consultant for achieving financial objectives; and (iii) to solidify the
long-term management structure of the Company.

         NOW, THEREFORE, the Company and the Consultant, for good and valuable
consideration, and pursuant to the terms, conditions, and covenants contained
herein, hereby agree as follows:

1. Section 3 of the Agreement, captioned "Term", shall be deleted in its
entirety and the following new language inserted in lieu thereof:

         "The term of this Agreement shall commence upon the day and year first
         above written ("Commencement Date") and shall continue until June 30,
         2002, unless sooner terminated, as provided herein."

2. Section 4 of the Agreement, captioned "Compensation", is amended by deleting
the compensation chart contained therein in its entirety and inserting the
following in lieu thereof:

<TABLE>
<CAPTION>
     ---------------------------------------------------------------------------
     Period                                                    Compensation
     ---------------------------------------------------------------------------
     <S>                                                       <C>
     July 1, 1995 through June 30, 1996                        $150,000
     ---------------------------------------------------------------------------
     July 1, 1996 through June 30, 1997                        $160,000
     ---------------------------------------------------------------------------
     July 1, 1997 through June 30, 1998                        $170,000
     ---------------------------------------------------------------------------
     July 1, 1998 through June 30, 1999                        $180,000
     ---------------------------------------------------------------------------
     July 1, 1999 through June 30, 2000                        $190,000
     ---------------------------------------------------------------------------
     July 1, 2000 through June 30, 2001                        $210,000
     ---------------------------------------------------------------------------
     July 1, 2001 through June 30, 2002                        $230,000
     ---------------------------------------------------------------------------
</TABLE>


3. Section 5 of the Agreement, captioned "Bonuses", is amended by deleting the
target bonus chart contained therein in its entirety, and inserting the
following in lieu thereof:

<TABLE>
<CAPTION>
     ---------------------------------------------------------------------------
     Fiscal Year Ending                                       Target Bonus
     ---------------------------------------------------------------------------
     <S>                                                      <C>
     June 30, 1996                                            $70,000
     ---------------------------------------------------------------------------
     June 30, 1997                                            $80,000
     ---------------------------------------------------------------------------
     June 30, 1998                                            $90,000
     ---------------------------------------------------------------------------
     June 30, 1999                                            $100,000
     ---------------------------------------------------------------------------
</TABLE>



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<PAGE>   2
<TABLE>
     ---------------------------------------------------------------------------
     <S>                                                       <C>
     June 30, 2000                                             $110,000
     ---------------------------------------------------------------------------
     June 30, 2001                                             $130,000
     ---------------------------------------------------------------------------
     June 30, 2002                                             $150,000
     ---------------------------------------------------------------------------
</TABLE>

4. The first paragraph of Section 13(c)(3) of the Agreement shall be deleted in
its entirety and the following new language inserted in lieu thereof:

         "Payment Upon Termination By The Company. If the Company terminates
         this Agreement for any reason other than Good Cause, the Consultant
         shall be entitled to receive from the Company and the Company shall pay
         to the Consultant in one lump sum, within fifteen (15) days following
         the termination of this Agreement, all of the compensation and Target
         Bonus payments provided for in Sections 4 and 5 of this Agreement for
         the period beginning on the date of the termination of the Agreement
         and ending on June 30, 2002."

5. The first paragraph of Section 13(c)(4) of the Agreement shall be deleted in
its entirety and the following new language inserted in lieu thereof:

         "Payment Upon Termination By The Consultant. If the Consultant
         terminates this Agreement for Good Reason, other than Good Reason
         described in Section 13(a)(3)a), he shall be entitled to receive from
         the Company and the Company shall pay to the Consultant in one lump
         sum, within fifteen (15) days following the date of the Consultant's
         termination of this Agreement, all of the compensation and Target Bonus
         payments provided for in Sections 4 and 5 of this Agreement for the
         period beginning on the date of the Consultant's termination of this
         Agreement and ending on June 30, 2002. If the Consultant terminates
         this Agreement for the Good Reason described in Section 13(a)(3)a),
         then and in such event, he shall be entitled to receive from the
         Company and the Company shall pay to the Consultant in one lump sum,
         within fifteen (15) days following the date of the Consultant's
         termination of this Agreement, an amount equal to the lesser of (i) all
         of the compensation and Target Bonus payments provided for in Sections
         4 and 5 of this Agreement for the period beginning on the date of the
         Consultant's termination and ending on June 30, 2002, or (ii) all of
         the compensation and Target Bonus payments provided for in Sections 4
         and 5 of this Agreement for the period commencing on the date of the
         Consultant's termination and ending on the third anniversary of the
         date of the Consultant's termination."

6. All other provisions of the Agreement shall remain in full force and effect.

         IN WITNESS WHEREOF, the parties have executed this First Amendment as
of the dates indicated below, the effective date of this First Amendment being
the first day of February, 1999.

                                    COMPANY:
ATTEST:                             MICROS SYSTEMS, INC.

-----------------                   By:                                   (SEAL)

                                    ----------------------
                                    A. L. Giannopoulos
                                    President and Chief 
                                    Executive Officer
[Corporate Seal]

                                    CONSULTANT:

WITNESS:

----------------                    -------------------------             (SEAL)
                                    Louis M. Brown, Jr.


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