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                                                                   EXHIBIT 10-15

                              EMPLOYMENT AGREEMENT


      EMPLOYMENT AGREEMENT ("Agreement") entered into and effective as of this
1st day of March, 1999, by and between SOMERSET MARINE, INC. ("Employer"), a New
York corporation with its principal place of business in New York, New York and
Salvatore A. Margarita (the "Executive").

                                    RECITALS

      WHEREAS, Employer desires to retain and employ the services of Executive
as Vice President of Employer; and

      WHEREAS, Executive has been employed by Employer for 15 years; and

      WHEREAS, the parties hereto wish to provide herein for the terms and
conditions of Executive's continued employment and to secure for Employer the
benefits of Executive's continued contributions by reason of Executive's
experience, skills and knowledge pertaining to Employer's business, and to
increase Executive's salary in exchange for Executive making a long term
commitment to Employer.

      NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, Employer and Executive agree as follows:

SECTION 1.  EMPLOYMENT.

(a) POSITION. Employer hereby employs Executive and Executive hereby accepts
such employment for the provision of executive services on behalf of Employer as
Vice President. Executive agrees to serve in such capacity with the duties set
forth in Section 1(b) for a term beginning on March 1, 1999, and ending on
December 31, 2001, unless renewed pursuant to Section 1(c) hereof, or terminated
pursuant to Section 5.

(b) DUTIES. Executive's duties and responsibilities shall be those consistent
with and appropriate to the position of Vice President, as may be established
and directed from time to time, by the Board of Directors. Executive shall
devote his full time and attention to his duties and responsibilities as Vice
President, which he will carry out to the best of his abilities. Executive shall
treat his position with Employer as his exclusive occupation and employment,
refraining from engaging in all other active business activities, except as may
be approved by Employer's Board of Directors.

(c) This Agreement may be renewed by the Employer by sending notice to Executive
at least 180 days prior to the end of the term set forth in Section 1(a), and
the Executive delivering written acceptance to Employer within 10 days of
receipt of such notice.
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SECTION 2. COMPENSATION.

      (a) ALLOCATION OF BASE ANNUAL SALARY. Employer shall pay to Executive
during the term of this Agreement a base annual salary of no less than $150,000.
Such base annual salary may be changed upon annual review by the Board of
Directors or its Compensation Committee. Such annual review shall occur prior to
the end of February each year beginning in the year 2000 for the express purpose
of considering increments. All compensation payments shall be paid in accordance
with Employer's regular payroll schedule and practice, and shall be subject to
all applicable withholding.

      (b) BONUSES. Executive shall be eligible to participate in and receive
periodic bonuses under Employer's current Bonus Payment Plan. In addition,
Employer, in its sole discretion, may elect to pay to Executive such periodic
bonuses as it deems appropriate.

      (c) BUSINESS EXPENSES. Upon presentation of appropriate documentation,
Employer shall reimburse Executive for expenses reasonably incurred in the
course of his employment, in accordance with policies established by Employer.

SECTION 3. BENEFITS

      In addition to the compensation specified in Section 2, Employer shall
provide Executive with the following fringe benefits:

      (a) EXECUTIVE BENEFITS. In addition to any other benefits provided in this
Section 3, Executive shall be entitled to those fringe benefits to which all
other employees of Employer are entitled during employment. Nothing in this
Agreement shall require the Employer to establish, maintain or continue any of
the fringe benefits already in existence or hereafter adopted for employees of
Employer and nothing in this Agreement shall restrict the right of the Employer
to amend, modify or terminate such fringe benefit programs.

      (b) VACATION. Executive shall be entitled to twenty two (22) days of
compensated vacation time in each year of this Agreement.

      (c) PROFESSIONAL MEETINGS. Executive shall be entitled to attend
professional meetings and to attend to such outside professional duties in the
insurance industry as may be appropriate and commensurate with his position
hereunder.

      (d) PROFESSIONAL DUES. Employer agrees to pay the applicable dues to
professional associations and societies of which Executive is a member.

      (e) INSURANCE. Employer shall provide insurance coverage (so long as all
other Employees of Employer are provided with such coverage) as follows:

      1.    Employer shall provide life insurance coverage for Executive in
            accordance with Employer's policy in an amount of $150,000, payable
            to the beneficiary or beneficiaries of his choice.


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      2.    Employer shall provide comprehensive health, major medical and
            long-term disability insurance for Executive and his family in
            accordance with Employer's group insurance plan.

      3.    Employer shall provide travel accident insurance covering Executive
            in accordance with Employer's standard policy.

SECTION 4. CONFIDENTIALITY

      While employed under this Agreement or at any time thereafter, Executive
agrees that he will not, directly or indirectly (other than in the performance
of the services under this Agreement), make or cause to be made any disclosure,
copy or other use not authorized by Employer of any confidential information
pertaining to Employer or any of its affiliates acquired during the course of
his employment by Employer, unless such information is or becomes otherwise
generally available to the public. For purposes of this Agreement, the term
"confidential information" means any business and financial information of any
nature not generally known to the public at large regarding the business and
operations of Employer or any of its affiliates.

SECTION 5. TERMINATION

      Executive's employment hereunder shall terminate as follows:

(a)   TERMINATION NOTICE. Either party may terminate Executive's employment,
      with or without cause, upon thirty (30) days written notice to the other
      party. Executive and Employer may agree that Executive may cease work
      after notice has been given but before the expiration of thirty (30) days
      in which case the effective date of the termination of Executive's
      employment shall be the date on which Executive ceases performing duties
      on behalf of Employer.

(b)   DEATH OR DISABILITY. Executive's employment shall terminate without notice
      upon Executive's date of death or disability as that term is defined
      herein. For purposes of this subsection, disability shall mean a period of
      six (6) consecutive months or an aggregate of eight (8) months in any
      twelve (12) consecutive month period during which Executive is disabled
      from performing his duties and responsibilities hereunder by reason of any
      illness, accident, injury or other health or medical condition of any
      kind.

(c)   WITH CAUSE. Employer may terminate this Agreement, without advance notice,
      upon a breach by Executive, for insubordination or disloyalty, for failure
      to follow the legal directives of the Board of Directors, or upon the
      conviction of Executive of any felony or of any criminal act in the course
      of, or pertaining to, Executive's employment hereunder. Such termination
      by Employer shall constitute a termination with cause.

(d)   CHANGE OF CONTROL; CHANGE OF EXECUTIVE'S DUTIES. In the event of a "change
      of control" of Employer, as such term is hereinafter defined, or a "change
      of Executive's duties" as such term is also hereinafter defined, Executive
      may, but shall not be required to, elect to terminate his employment
      hereunder and treat the termination of such employment as a termination by
      Employer without cause. Any such election must be made within one (1) year


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      from the date of occurrence of the events giving rise to either a change
      of control of Employer or a change of Executive's duties. In such event,
      Executive shall provide to Employer the thirty (30) day notice referred to
      in subsection (a) above, indicating his election to treat such termination
      of employment as a termination by Employer without cause.

For purposes of this Agreement, a "change of control" of Employer shall be
deemed to have occurred in the event of the occurrence of any of the following:
(i) the sale of 50% or more of the common stock, or the assets, of The
Navigators Group, Inc., to parties unaffiliated with Terence N. Deeks, in a
transaction or series of transactions occurring within a one year period; (ii) a
merger of Employer with any other entity, such that the other entity or any of
its parents or affiliates have the right to control the business operations of
Employer or, as a result of such a merger, Employer is not the surviving or
continuing business entity.

      For purposes of this Agreement, a change of Executive's duties shall be
deemed to have occurred in the event of the Executive's duties and
responsibilities are materially reduced and a significant portion of his duties
and responsibilities are assigned to one or more other employees of Employer.

(e)   WITHOUT CAUSE. Except as set forth in subsections (b) and (c) above, the
      termination of Executive's employment by Employer shall constitute a
      termination without cause.

SECTION 6.  EFFECT OF TERMINATION; SEVERANCE BENEFITS

(a)   TERMINATION BENEFITS FOR TERMINATION WITHOUT CAUSE. If Employer terminates
      the employment of Executive without cause, Executive shall be entitled to
      receive from Employer:

1.    An amount equal to one year's base salary, as in effect for the twelve
      (12) month period immediately preceding the effective date of such
      termination of employment.

2.    Executive shall be entitled to continued comprehensive health and major
      medical insurance coverage, at Employer's cost, under Employer's group
      insurance plan, COBRA if necessary, for a period of six (6) months after
      the effective date of such termination of employment. Thereafter, to the
      extent eligible, Executive may continue such coverage, at his own cost,
      under COBRA.

3.    During the period that termination benefits are paid under this Agreement,
      Executive shall not be required to perform any duties for Employer or
      report to the Employer offices.

4.    Employer shall pay to Executive the termination benefit referred to in
      Section (a)(1) above by either paying such sum in installments on
      Employer's regular payroll dates for the one-year period in question, or,
      alternatively, with the Executive's prior written consent, to prepay such
      benefits in a single lump-sum amount, actuarially reduced by reason of
      such prepayment. In the event that Employer pays such sum in installments
      on its regular payroll dates, as aforesaid, and only in such event, if
      Executive shall accept full-time employment during the period in which
      such payments are being made, then Executive shall, within ten (10) days
      of accepting such employment, advise Employer of such fact, indicating the
      name and address of his new Employer and the amount of his salary. If
      Executive's salary at his


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      new place of employment is equal to or greater than his last salary at
      Employer, the payment by Employer of the termination benefit and the
      providing to Executive of continued comprehensive healthcare and major
      medical benefits under Employer's plan and at its expense shall terminate
      upon the commencement of Executive's new employment. If Executive's salary
      in his new position is less than his last salary at Employer, Employer's
      continuing installment payments to Executive shall be reduced so as to pay
      to Executive the difference between his salary rate at his new place of
      employment and his last salary rate at Employer. Employer's continuation
      of comprehensive healthcare and major medical benefits shall also
      terminate at the commencement of Executive's new employment, unless he is
      not receiving comparable healthcare insurance benefits under his new
      Employer's insurance plan.

(b)   NO BENEFITS FOR WITH CAUSE TERMINATION. Upon termination of this Agreement
      by Employer with cause, under the provisions of Section 5(c), or the
      termination of this Agreement by reason of Executive's death or disability
      under Section 5(b) (provided that Employer has a disability insurance
      policy in force for the benefit of Employee at such time as Employee
      claims disability), Employer shall not be obligated to pay to Executive
      (or his estate or representative in the event of his death) any
      termination benefits and Employer's obligations hereunder shall terminate
      with the effective date of the termination of the Executive's employment.
      However, Executive's obligations and covenants under Section 4 shall
      continue in full force and effect and shall survive the termination of
      Executive's employment.

SECTION 7.  MISCELLANEOUS

(a)   SOLE AGREEMENT; AMENDMENT. This Agreement constitutes the entire agreement
      of the parties, supersedes all prior agreements and understandings, and
      may be amended only by a written agreement executed by both of the parties
      hereto.

(b)   SEVERABILITY. The invalidity or unenforceability of any particular
      provision of this contract shall not affect its other provisions, and this
      Agreement shall be construed in all respects as if such invalid or
      unenforceable provision had been omitted.

(c)   SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon and inure to
      the benefit of each of the parties hereto, their successors and assigns,
      administrators, executors, legatees, and representatives, including,
      without limitation, any corporation into which Employer may be merged or
      by which it may be acquired.

(d)   FORUM. This Agreement shall be construed and enforced under and in
      accordance with the internal laws of the State of New York.

(e)   COUNSEL. Each of the parties have read this Agreement and execute it after
      having an opportunity to consult with counsel.

(f)   NOTICES. Any and all notices required to be given under this Agreement
      shall be given by, and be deemed given when, (i) delivered by personal
      delivery; (ii) deposited in U.S. first-class mail, postage prepaid; or
      (iii) sent by telecopy with confirmation of receipt and by first class
      mail, postage prepaid, addressed as follows:


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      If to Employer:   Somerset Marine, Inc.
                        123 William Street
                        New York, NY 10038
                        Attention: Terence N. Deeks
                        Fax: 212-346-6820


      If to Executive:  Mr. Salvatore A. Margarella
                        123 William Street
                        New York, NY 10038


or such other address as a party may designate in writing to the other party.

                                   SIGNATURES


      IN WITNESS WHEREOF, the parties have executed this Agreement effective as
of the date first set forth above.



SOMERSET MARINE, INC.               EXECUTIVE:


BY: /s/ Terence N. Deeks                  /s/ Salvatore A. Margarella
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DATE: March 1, 1999                       DATE: March 3, 1999
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