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                                                                  EXHIBIT 10.18
 
                             EMPLOYMENT AGREEMENT
 
  Agreement effective November 1, 1998, between MapInfo Corporation, One
Global View, Troy, New York 12180 ("MapInfo" or "Company"), and John C.
Cavalier, an individual residing at 42 East Ridge Road, Loudonville, New York
12211 ("Cavalier").
 
1.0 EMPLOYMENT AND TERM
 
  1.1 MapInfo agrees to continue to employ Cavalier as President and Chief
Executive Officer of the Company for a period of three years from November 1,
1998 to November 1, 2001 (the "Contract Expiration Date").
 
  1.2 Cavalier agrees to continue to aid in managing the operations of MapInfo
under the supervision of the Board of Directors of MapInfo, to serve as a
member of the MapInfo Board of Directors, to perform such other services as
shall from time to time be assigned to him by the Board of Directors, and to
diligently and competently devote his entire business time, skill and
attention to such services.
 
2.0 COMPENSATION AND BENEFITS
 
  2.1 The Company shall pay to Cavalier a base salary of not less than
$275,000 per annum, in accordance with the standard payroll practices of the
Company. Cavalier's annual salary may be increased from time to time in
accordance with the normal business practices of the Company and, if so
increased, shall not thereafter be decreased, except by the mutual agreement
of the parties.
 
  2.2 The Company shall reimburse Cavalier 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 MapInfo.
 
  2.3 Cavalier shall be entitled to participate on the same basis, subject to
the same qualifications, as other employees of the Company in any disability,
pension, life insurance, health insurance, hospitalization and other fringe
benefit plans in effect with respect to other employees of the Company, in
accordance with the written terms of said plans which shall be controlling.
 
  2.4 The Company shall purchase such additional medical, disability, life
insurance and/or other fringe benefit programs of Cavalier's choosing up to a
maximum amount of $ 35,000 per annum. Additionally the Company requires, and
shall pay all expenses of, an annual physical for Cavalier at the Mayo Clinic,
to the extent such expenses are not covered by the Company's existing health
insurance plan. The income tax implications of all of this compensation shall
be the responsibility of Cavalier.
 
  2.5 In addition to his salary, Cavalier 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 Cavalier's performance during each fiscal year as follows:
 
    2.5.1 an additional one-half of Cavalier's annual base salary may be
  earned, payable quarterly, for achieving targeted Company and personal
  objectives, and another additional one-half annual base salary may be
  earned, payable not later than forty-five (45) days after the end of the
  fiscal year, for achieving super objectives; and
 
    2.5.2 Cavalier's annual incentive compensation target may be increased
  from time to time in accordance with the normal business practices of the
  Company and, if so increased, shall not thereafter be decreased below the
  initial incentive compensation plan of this Agreement (section 2.5.1 above)
  except by written mutual agreement of the parties.
 
 
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    2.6 Also in addition to his salary, Cavalier shall be granted one hundred
  thousand (100,000) non-qualified stock options under the MapInfo 1993 Stock
  Incentive Plan (the "Plan") in accordance with the provisions of the Plan,
  a copy of which has been received by Cavalier, with:
 
      2.6.1 the exercise price of the options set at the fair market value
    of MapInfo Common Stock on November 1, 1998; and
 
      2.6.2 twenty-five thousand (25,000) of the options shall fully vest
    on October 31, 2000, and the remaining seventy-five thousand (75,000)
    shall fully vest on October 31, 2001.
 
3.0 INTELLECTUAL PROPERTY, CONFIDENTIAL INFORMATION AND NON-COMPETITION
 
  Cavalier reaffirms his previously executed attached Employee Intellectual
Property, Confidential Information and Non-Competition Agreement.
 
4.0 IRREPARABLE INJURY
 
  4.1 Both parties hereto recognize that the services to be rendered by
Cavalier during the term of his employment are special, unique and of
extraordinary character, and Cavalier acknowledges that any violation by him
of Section 3 of this Agreement may cause the Company irreparable injury.
 
  4.2 In the event of a breach or threatened breach by Cavalier of the
provisions of said Section 3, MapInfo shall be entitled to an injunction
restraining Cavalier from violating the terms thereof, and from providing any
confidential information to any person, firm, corporation, association or
other entity, whether or not Cavalier is then employed by, or an officer,
director, or owner thereof.
 
  4.3 Nothing herein shall be construed as prohibiting the Company from
pursuing any other remedies available to it for such breach or threatened
breach, including recovery of damages from Cavalier.
 
5.0 EARLY TERMINATION
 
  Definitions for purposes of this Agreement:
 
    "CAUSE" shall be defined and limited to (i) the willful and continued
  failure by Cavalier to substantially perform his duties hereunder (other
  than any such failure resulting from Cavalier's incapacity due to physical
  or mental illness), or (ii) conviction for any crime other than simple
  offenses or traffic offenses or misdemeanors that could not relate to
  performance or harm the Company in any way; or (iii) breach of Cavalier's
  fiduciary responsibilities to the Company; or (iv) conduct reflecting moral
  turpitude; or (v) commission of fraud or gross misconduct in Cavalier's
  dealings with or on behalf of the Company; or (vi) breach of any duty of
  confidentiality owned the Company.
 
    "CHANGE IN CONTROL OF THE COMPANY" shall mean an acquisition (directly or
  indirectly) resulting in more than 50% of the Company's voting stock or
  assets being acquired by one or more entities that thereby gain management
  control of the Company. This section shall govern in case of any conflict
  between the wording of this Agreement and the wording of the plan under
  which any options were granted to Cavalier.
 
    "GOOD REASON" shall mean a failure by the Company to comply with any
  material provision of this Agreement which has not been cured within ten
  (10) days after Cavalier has given written notice of such noncompliance to
  the Company.
 
    "NOTICE OF TERMINATION" shall mean a written notice to the other party
  that Cavalier is either terminating or to be terminated for one of the
  reasons set forth in this Agreement.
 
 
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  5.1 Cavalier's employment hereunder may be terminated prior to the Agreement
Expiration Date only under any one of the following circumstances:
 
    5.1.1 the death of Cavalier;
 
    5.1.2 a mental, physical or other disability or condition of Cavalier
  which renders him incapable of performing his obligations under this
  Agreement for a period of three (3) consecutive months;
 
    5.1.3 by Cavalier for either (i) Good Reason or (ii) a Change in Control
  of the Company;
 
    5.1.4 by the Company for Cause.
 
  5.2 Any termination of Cavalier's employment by the Company or by Cavalier
shall be communicated by written Notice of Termination to the other party
hereto.
 
  5.3 "DATE OF TERMINATION" shall mean:
 
    5.3.1 if Cavalier's employment is terminated by his death, the date of
  his death;
 
    5.3.2 if Cavalier's employment is terminated by reason of the event
  specified in subsection 5.1.2 above, thirty (30) days after Notice of
  Termination is given (provided that Cavalier shall not have returned to the
  performance of his duties on a full-time basis during such thirty (30) day
  period);
 
    5.3.3 if Cavalier's employment is terminated for Cause pursuant to
  subsection 5.1.4. above, the date the Notice of Termination is given or
  later if so specified in such Notice of Termination; and
 
    5.3.4 if Cavalier's employment is terminated for any other reason, the
  date on which a Notice of Termination is given.
 
  5.4 If within thirty (30) days after any Notice of Termination is given the
party receiving such Notice of Termination notifies 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.
 
6.0COMPENSATION UPON EARLY TEMINATION OR DISABILITY
 
  6.1 During any period that Cavalier fails to perform his duties hereunder as
a result of incapacity due to physical or mental illness ("disability
period"), he shall continue to receive his full salary at the rate then in
effect for such period until his employment is terminated pursuant to section
5.1.2 above, provided that payments so made to Cavalier during the disability
period shall be reduced by the sum of the amounts, if any, payable to Cavalier
at or prior to the time of any such payment under disability benefit plans of
the Company, and which were not previously applied to reduce any such payment.
 
  6.2. If Cavalier's employment is terminated by his death, the Company shall
have no further payment obligations to Cavalier other than those arising from
his employment prior to his death.
 
  6.3 If Cavalier's employment shall be terminated for Cause, the Company
shall pay Cavalier 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 Section 2.5 through the Date of Termination, and the
Company shall have no further obligations to Cavalier under this Agreement.
 
  6.4 If Cavalier shall terminate his employment by resigning for other than
Good Reason, the Company shall pay Cavalier his full salary through the Date
of Termination at that rate in effect when the Notice of Termination is given,
and any incentive compensation earned under Section 2.5 as of the Date of
Termination.
 
  6.5 If Cavalier's employment shall be terminated by MapInfo for reasons
other than pursuant to Sections 5.1.1, 5.1.2 or 5.1.4 hereof or if Cavalier
shall terminate his employment for Good Reason, then
 
    6.5.1 the Company shall pay to Cavalier, in a lump sum at the option of
  Cavalier and then within fourteen (14) days following the Date of
  Termination, his full salary due to the end of the contract period
 
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  (October 31, 2001), at the rate in effect at the time Notice of Termination
  is given, but in any event not less than one full year of salary regardless
  of the remaining number of months under this Agreement, together with any
  incentive compensation earned under Section 2.1.5 as of the Date of
  Termination; and
 
    6.5.2 the Company shall continue Cavalier's health and dental insurance
  coverage for the one year period following the Date of Termination on the
  same terms as provided to other MapInfo employees.
 
  6.6 Upon any Change in Control of the Company, where Cavalier is not the
surviving CEO, or is offered a position not equivalent to his present
position, then, at his option, his employment shall terminate upon such change
in control; and:
 
    6.6.1 The Company shall pay to Cavalier, in a lump sum at his option
  within fourteen (14) days following the Date of Termination:
 
      6.6.1.1 his full base salary due through the end of the contract
    period (October 31, 2001), at the rate in effect at the time Notice of
    Termination is given, but in any event not less than one full year of
    salary regardless of the remaining number of months under this
    Agreement; and
 
      6.6.1.2 an additional payment that is equal to the average of the
    incentive compensation paid to Cavalier during the preceding two full
    contract employment years divided by twelve (12), and multiplied by the
    months remaining on the term of this contract; and
 
    6.6.2 The Company shall continue, for a period of one year from the Date
  of Termination, to pay for Cavalier's group health and group life
  insurance, or provide equivalents thereof.
 
  6.7 Upon any Change in Control of the Company, all unexpired and unvested
options of Cavalier to purchase common stock of the Company shall become
exercisable immediately as of the date of such Change in Control, for such
period of time and upon such terms as are provided in the Plan under which the
options were granted.
 
7.0 NOTICES
 
  All communications and notices hereunder shall be in writing and either
personally delivered or mailed to the party at the address set forth above.
Notices to MapInfo shall be addressed to the attention of the Chairman with a
copy to the Executive Vice President/CFO.
 
8.0 ENTIRE AGREEMENT, NO WAIVER
 
  This Agreement and the agreements referred to herein constitute the entire
understanding between that parties and supersede all prior agreements or
understandings between the parties except as to matters that that may be
ongoing, such as but not limited to the forgiveness of debt agreed to in the
initial Employment Agreement between the parties. 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.
 
9.0 SUCCESSORS
 
  9.1 The Company 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 Company, by agreement in form and substance
satisfactory to Cavalier, to expressly assume and agree to perform this
Agreement in the same manner and to the same extent that the Company would be
required to perform it if no such succession had taken place. Failure of the
Company (or any successor to its business and/or assets) to obtain such
agreement prior to the effectiveness of any such succession shall, at
Cavalier'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.
 
 
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  9.2 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 Section 9, this Agreement may not be assigned by either of
the parties hereto. If Cavalier 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 Cavalier's
previously determined designee or, if there be no such designee, to Cavalier's
estate.
 
10.0 ARBITRATION
 
  10.1 Except as otherwise provided in Section 4.0 above, any dispute or claim
relating to or arising out of the employment of the Company, 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
 
  10.2 The arbitrators shall have jurisdiction to determine any such claim,
and may grant any relief authorized by law for such claim with their decision
based on and supported by written findings of fact and conclusions of law
 
  10.3 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.
 
11.0 GOVERNING LAW
 
  This Agreement shall be governed by, and construed in accordance with, the
laws of the State of Delaware 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.
 
                                         MAPINFO CORPORATION
 
         /s/ John C. Cavalier             BY:      /s/ Michael D. Marvin
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           JOHN C. CAVALIER                        Chairman of the Board
 
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