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                                                                  EXHIBIT 10.24
 
                             EMPLOYMENT AGREEMENT
 
  Agreement made as of September 27, 1996, between MAPINFO CORPORATION, One
Global View, Troy, New York 12180 ("MapInfo" or "Company"), and John C.
Cavalier, an individual residing at 3804 Silver Falls Court, Plano, Texas (the
"Employee").
 
1. EMPLOYMENT AND TERM.
 
  MapInfo agrees to employ the Employee as President and Chief Executive
Officer of the corporation for a period of two years, beginning on the date
employment commences and ending two years later (the "Contract Expiration
Date"). The Employee agrees to commence such employment on or before November
4, 1996, agrees to aid in managing the operations of MapInfo under the
supervision of the Board of Directors of MapInfo, agrees to serve as a member
of the Board of Directors of the Corporation, agrees to perform such other
services as shall from time to time be assigned to him by the Board of
Directors, and agrees to devote diligently and competently, his entire
business time, skill and attention to such services.
 
2. COMPENSATION AND BENEFITS.
 
  A. The Employer shall pay to the Employee a salary of not less than
     $250,000 per annum. Employee's salary shall be payable in accordance
     with the standard payroll practices of the Employer. The Employee's
     annual salary may be increased from time to time in accordance with the
     normal business practices of the Employer and, if so increased, shall
     not thereafter be decreased, except by the mutual agreement of the
     parties.
 
  B. The Employer shall reimburse the Employee for all reasonable out-of-
     pocket expenses incurred in connection with the performance of his
     duties hereunder, payable in accordance with the standard expense
     account procedures of the Employer.
 
  C. The Employee shall be entitled to participate on the same basis, subject
     to the same qualifications, as other employees of the Employer in any
     disability, pension, life insurance, health insurance, hospitalization
     and other fringe benefit plans in effect with respect to employees of
     the Employer, in accordance with the written terms of said plans which
     shall be controlling.
 
  D. The Employer shall purchase such additional medical, disability, life
     insurance or any other fringe benefit programs of the Employee's
     choosing up to a maximum amount of $20,000 per annum. The income tax
     implications of this compensation shall be the responsibility of
     Employee.
 
  E. In addition to his salary, the Employee will be eligible to earn each
     year during the term of his employment incentive compensation in amounts
     to be determined by the Compensation Committee of the Board of Directors
     based on the Company's and the Employee's performance during each fiscal
     year. $125,000 per annum may be earned, payable quarterly, for achieving
     targeted Company and personal objectives and $125,000 per annum may be
     earned, payable 45 days after the end of the fiscal year, for achieving
     super objectives. Incentive compensation for the fiscal year ending
     September 30, 1997 shall be prorated from the Employee's first day of
     full time employment under this Agreement. The Employee's annual
     incentive compensation target may be increased from time to time in
     accordance with the normal business practices of the Employer and, if so
     increased, shall not thereafter be decreased, except by the mutual
     agreement of the parties.
 
  F. On the earlier of (a) the commencement date of a consulting engagement
     between Cavalier and MapInfo and (b) the Employee's first day of
     employment, the Employee shall be granted 200,000 non-qualified stock
     options under the 1993 Stock Incentive Plan in accordance with the
     provisions of the attached plan. The exercise price of the options shall
     be the fair market value of MapInfo Common Stock on the date of the
     option grant. 25% of such options will vest on each of the four
     anniversary dates of the grant date.
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  G. To assist in relocation, Employee shall be entitled to borrow up to
     $200,000 from MapInfo at no (0%) interest for expenses reasonably
     incurred by him in relocating his immediate family, including costs of
     selling his present Texas residence, closing costs on the purchase of
     new home in the Capital District, moving household goods, temporary
     living costs during the relocation period, other reasonable incidental
     costs, and the personal tax consequences thereof. One half of such loan
     will be forgiven on the one year anniversary date of Employee's
     permanent relocation to the Capital District, provided he is employed by
     MapInfo at that time. The second half will be forgiven on the second
     anniversary date of Employee's permanent relocation to the Capital
     District provided he is employed by MapInfo at that time. If the
     Employee was terminated by the Employer for other than Cause, the loan
     shall be forgiven. In all other instances of termination of employment
     prior to that second anniversary date, the loan will be immediately due
     and payable.
 
3. INTELLECTUAL PROPERTY, CONFIDENTIAL INFORMATION AND NON-COMPETITION.
 
  The Employee shall have executed the attached Employee Intellectual
Property, Confidential Information and Non-Competition Agreement prior to
commencement of employment.
 
4. IRREPARABLE INJURY.
 
  The Employee acknowledges that any violation by him of Article 3 of this
Agreement may cause the Employer irreparable injury. In the event of a breach
or threatened breach by the Employee of the provisions of Article 3 of this
Agreement, the Employer shall be entitled to an injunction restraining the
Employee from violating the terms thereof, from disclosing to any person,
firm, corporation, association or other entity, whether or not the Employee is
then employed by, or an officer, director, or owner thereof, any Proprietary
Information. Nothing herein shall be construed as prohibiting the Employer
from pursuing any other remedies available to it for such breach or threatened
breach, including recovery of damages from the Employee. Both parties hereto
recognize that the services to be rendered by the Employee during the term of
his employment are special, unique and of extraordinary character.
 
5. EARLY TERMINATION.
 
  A. The Employee's employment hereunder may be terminated prior to the
     Contract Expiration Date only under the following circumstances:
 
    1. The death of the Employee;
 
    2. A mental, physical or other disability or condition of the Employee
       which renders the Employee incapable of performing his obligations
       under this Agreement for a period of three (3) consecutive months;
 
    3. By the Employee for Good Reason. For purposes of this Agreement,
       "Good Reason" shall mean (i) a failure by the Employer to comply
       with any material provision of this Agreement which has not been
       cured within ten (10) days after written notice of such
       noncompliance has been given by the Employee to the Employer, or
       (ii) a change in control of Employer.
 
    4. By the Employer for Cause. For purposes of this Agreement, the
       Employer shall have "Cause" to terminate the Employee's employment
       hereunder upon (a) the willful and continued failure by the Employee
       to substantially perform his duties hereunder (other than any such
       failure resulting from the Employee's incapacity due to physical or
       mental illness), or (b) the willful engaging by the Employee in
       misconduct which is materially injurious to the Employer, monetarily
       or otherwise, or (c) of the willful violation by the Employee of the
       provisions of the Nondisclosure Agreement.
 
  B. Any termination of the Employee's employment by the Employer or by the
     Employee shall be communicated by written Notice of Termination to the
     other party hereto.
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  C. "Date of Termination" shall mean (1) if the Employee's employment is
     terminated by his death, the date of his death, (2) if the Employee's
     employment is terminated by reason of the event specified in subsection
     A.2. above, thirty (30) days after Notice of Termination is given
     (provided that the Employee shall not have returned to the performance
     of his duties on a full-time basis during such thirty (30) day period),
     (3) if the Employee's employment is terminated for Cause pursuant to
     subsection A.3. above, the date the Notice of Termination is given or
     later if so specified in such Notice of Termination, and (4) if the
     Employee's employment is terminated for any other reason, the date on
     which a Notice of Termination is given. If within thirty (30) days after
     any Notice of Termination is given the party receiving such Notice of
     Termination notified the other party that a dispute exists concerning
     the termination, the Date of Termination shall be the date fixed, either
     by arbitration award or by a final judgment, order or decree of a court
     of competent jurisdiction.
 
6. COMPENSATION UPON EARLY TEMINATION OR DISABILITY.
 
  A. During any period that the Employee fails to perform his duties
     hereunder as a result of incapacity due to physical or mental illness
     ("disability period"), the Employee shall continue to receive his full
     salary at the rate then in effect for such period until his employment
     is terminated pursuant to Article 5, subsection A.2. hereof, provided
     that payments so made to the Employee during the disability period shall
     be reduced by the sum of the amounts, if any, payable to the Employee at
     or prior to the time of any such payment under disability benefit plans
     of the Employer and which were not previously applied to reduce any such
     payment.
 
  B. If the Employee's employment is terminated by his death, the Employer
     shall have no further payment obligations to Employee other than those
     arising from his employment prior to his death.
 
  C. If the Employee's employment shall be terminated for Cause, the Employer
     shall pay the Employee his full salary through the Date of Termination
     at the rate in effect at the time Notice of Termination is given, and
     any incentive compensation earned under Article 2, section E through the
     Date of Termination and the Employer shall have no further obligations
     to the Employee under this Agreement.
 
  D. If the Employee shall terminate his employment by resigning for other
     than Good Reason, the Employer shall pay the Employee his full salary
     through the Date of Termination at that rate in effect at the Notice of
     Termination is given, and any incentive compensation earned under
     Article 2, section E as of the Date of Termination.
 
  E. If (1) the Employee's employment shall be terminated by MapInfo for
     reasons other than pursuant to Article 5, section A.1, A.2 or A.4 hereof
     or (2) if the Employee shall terminate his employment for Good Reason,
     then
 
    a) the Employer shall pay the Employee his full salary through the Date
       of Termination at the rate in effect at the time Notice of
       Termination is given, and any incentive compensation earned under
       Article 2, section E as of the Date of Termination;
 
    b) the Employer shall, in addition, pay as severance pay to the
       Employee a sum equal to the Employee's annual salary in effect at
       the Date of Termination in a lump sum on or before the tenth day
       following the Date of Termination;
 
    c) and the Employer shall continue the Employee's health and dental
       insurance coverage for the one year period following the Date of
       Termination on the same terms as provided to other employees of the
       Employer.
 
  F. Upon any change in control of the Employer, all outstanding stock
     options of Employee to purchase common stock of Employer not theretofore
     exercisable by Employee shall be and become immediately exercisable as
     of the date of such change in control of Employer for such period and
     upon such terms that are provided in the stock option plan.
 
7. NOTICES.
 
  All communications and notices hereunder shall be in writing.
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8. ENTIRE AGREEMENT.
 
  This Agreement and the agreements and exhibits referred to herein constitute
the entire understanding between that parties and supersede and cancel all
prior agreements or understandings between the parties hereto. No waiver or
modification of the terms hereof shall be valid unless in writing signed by
both parties hereto and only to the extent therein set forth.
 
9. SUCCESSORS.
 
  A. The Employer will require any successor (whether direct or indirect, by
     purchase, merger, consolidation or otherwise) to all or substantially
     all of the business and/or assets of the Employer, by agreement in form
     and substance satisfactory to the Employee, to expressly assume and
     agree to perform this Agreement in the same manner and to the same
     extent that the Employer would be required to perform it if no such
     succession had taken place. Failure of the Employer to obtain such
     agreement prior to the effectiveness of any such succession shall, at
     Employee's option to treat it as such, be a breach of this Agreement,
     except that for the purposes of implementing the foregoing, the date on
     which any such succession becomes effective shall be deemed the Date of
     Termination. As used in this Agreement, "Employer" shall mean the
     Employer as herein above defined and any successor to its business
     and/or assets as aforesaid which executes and delivers the agreement
     provided for in this Article 9 or which otherwise becomes bound by all
     the terms and provisions of this Agreement by operation of the law.
 
  B. This Agreement shall be binding upon and inure to the benefit of the
     parties hereto, their respective heirs, administrators, executors,
     personal representatives, successors and assigns; provided, however,
     that except as provided in this Article 9, this Agreement may not be
     assigned by either of the parties hereto. If the Employee should die
     while any amounts would still be payable to him, all such amounts
     earned, unless otherwise provided herein, shall be paid in accordance
     with the terms of this Agreement to the Employee's designee or, if there
     be no such designee, to the Employee's estate.
 
10. ARBITRATION.
 
  Except as otherwise provided in Article 4, any dispute or claim relating to
or arising out of the employment of the Employer, whether based on contract or
tort or otherwise, but not including statutory claims, shall be subject to
final and binding arbitration in the State of New York in accordance with the
applicable commercial arbitration rules of the American Arbitration
Association in effect at the time the claim or dispute arose. The arbitrators
shall have jurisdiction to determine any such claim, and may grant any relief
authorized by law for such claim. The arbitrators' decision shall be based on
and supported by written findings of fact and conclusions of law. Any claim or
dispute subject to arbitration shall be deemed waived, and shall be forever
barred, if arbitration is not initiated within twelve (12) months of the date
the claim or dispute first arose.
 
11. GOVERNING LAW.
 
  This Agreement shall be governed by, and construed in accordance with, the
laws of the State of New York without regard to the choice of law provisions
thereof.
 
IN WITNESS WHEREOF, the parties hereto have executed this Employment Agreement
as of the date and year first written above.
 
EMPLOYEE:
 
                                          MAPINFO:
 
/s/ John C. Cavalier 9/28/96              /s/ Michael D. Marvin 10/1/96
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John C. Cavalier                          By __________________________________