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                                                                  EXHIBIT 10-11



            FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT


            FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT dated as of
April 9, 1997 ("First Amendment") among THE NAVIGATORS GROUP, INC. (the
"Borrower"), BROWN BROTHERS HARRIMAN & CO., ("BBH&Co."), NBD BANK (formerly NBD
BANK, N.A.; "NBD"), FIRST UNION NATIONAL BANK OF NORTH CAROLINA ("First Union")
(each of BBH&Co., NBD and First Union a "Lender" and, collectively, the
"Lenders"), THE FIRST NATIONAL BANK OF CHICAGO, as issuer of Letters of Credit
(as defined in the Credit Agreement referred to below) ("Issuing Bank") and
BROWN BROTHERS HARRIMAN & CO., as agent for the Lenders and the Issuing Bank (in
such capacity, together with its successors and assigns in such capacity, the
"Agent").

            PRELIMINARY STATEMENT. Reference is made to the Amended and Restated
Credit Agreement dated as of November 26, 1996 among the Borrower, the Lenders,
the Issuing Bank and the Agent (the "Credit Agreement"). Any term used herein
and not otherwise defined herein shall have the meaning assigned to such term in
the Credit Agreement.

            Each of the parties hereto have agreed to amend certain provisions
of the Credit Agreement as hereinafter set forth.

            SECTION 1. Amendments to Credit Agreement. The Credit Agreement is,
effective as of this date hereof and subject to the satisfaction of the
conditions precedent set forth in Section 2 hereof, hereby amended as follows:

            (a) The following definition is added in its proper alphabetical
order:

                       "Significant Subsidiary" shall mean a Subsidiary of the
            Borrower (1) the assets of which are greater than or equal to ten
            percent (10%) of the aggregate assets of the Borrower and its
            Consolidated Subsidiaries or (2) the revenues of which are greater
            than or equal to ten percent (10%) of the aggregate revenues of the
            Borrower and its Consolidated Subsidiaries.

            (b) Section 7.12. Amendments to Borrower Pledge Agreement, shall be
amended by (i) deleting "January 31, 1997" in the first line thereof and
inserting in its place the following: "August 21, 1997", (ii) deleting each
reference to "Somerset Asia Pacific Pty. Ltd." contained therein, and (iii)
inserting at the end thereof the
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following:

            "Once Somerset Asia Pacific Pty. Ltd. becomes a Significant
            Subsidiary, the Borrower shall satisfy the following conditions with
            regard to its pledge of the stock of Somerset Asia Pacific Pty. Ltd:

            (1) Amendment to Borrower Pledge Agreement. The Borrower shall
            execute and deliver an amendment to the Borrower Pledge Agreement in
            form and substance satisfactory to the Lenders to effect a pledge of
            the stock of Somerset Asia Pacific Pty. Ltd. and the Borrower will
            deliver the certificates representing the shares pledged pursuant to
            such amendment to Borrower Pledge Agreement and undated stock powers
            executed in blank for each such certificate and the Borrower will
            take any and all other actions and execute any other agreements
            required to give the Agent a first priority perfected security
            interest in such stock; and

            (2) Opinion of Counsel. The Borrower shall deliver an opinion of
            counsel, dated the date of such pledge of stock, in a form
            acceptable to the Lenders, covering among other items, the
            perfection of the Agent's security interest in such stock."

            SECTION 2. Conditions of Effectiveness. This First Amendment shall
become effective on the date on which each of the following conditions has been
fulfilled:

            (1) First Amendment. The Borrower, the Lenders, the Issuing Bank and
the Agent shall each have executed and delivered this First Amendment;

            (2) First Amendment to Pledge Agreement. The Borrower shall have
executed and delivered the First Amendment to Pledge Agreement, together with
the certificates representing the shares pledged pursuant to such First
Amendment to Pledge Agreement and undated stock powers executed in blank for
each such certificate;

            (3) Evidence of All Corporate Action of the Borrower. Certified
copies, dated the date hereof, of all corporate action taken by the Borrower,
including resolutions of its Board of Directors, authorizing the execution,
delivery, and performance of this First Amendment and each of the documents
being delivered in connection herewith;

            (4) Opinion of Counsel. A favorable opinion of LeBoeuf, Lamb, Greene
& MacRae, L.L.P., counsel for the


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Borrower dated the date hereof;

            (5) Officer's Certificate, etc. The following statements shall be
true and the Agent shall have received a certificate signed by a duly authorized
officer of the Borrower dated the date hereof stating that, after giving effect
to this First Amendment and the transactions contemplated hereby:

            (a)   The representations and warranties contained in the Credit
                  Agreement and in each of the Loan Documents are correct on and
                  as of the date hereof as though made on and as of such date;
                  and

            (b)   No Default or Event of Default has occurred and is continuing.

            (6) Additional Documentation. The Agent shall have received such
other approvals, opinions or documents as any Lender or the Issuing Bank may
reasonably request.

            SECTION 3. Reference to and Effect on the Loan Documents. (a) Upon
the effectiveness of Section 1 hereof, on and after the date hereof each
reference in the Credit Agreement to "this Agreement", "hereunder", "hereof",
"herein" or words of like import, and each reference in the other Loan Documents
to the Credit Agreement, shall mean and be a reference to the Credit Agreement
previously amended and as amended hereby.

            (b) Except as specifically amended above, the Credit Agreement and
all other Loan Documents shall remain in full force and effect and are hereby
ratified and confirmed.

            (c) The execution, delivery and effectiveness of this First
Amendment shall not operate as a waiver of any right, power or remedy of the
Lenders, the Issuing Bank or the Agent under any of the Loan Documents, nor
constitute a waiver of any provision of any of the Loan Documents.

            SECTION 4. Costs, Expenses and Taxes. The Borrower agrees to pay on
demand all costs and expenses of the Agent in connection with the preparation,
reproduction, execution and delivery of this First Amendment and the other
instruments and documents to be delivered hereunder (including the fees and
out-of-pocket expenses of external counsel for the Agent, but not the legal fees
for internal or external legal counsel of the Lenders), with respect thereto.
In addition, the Borrower shall pay any and all stamp and other taxes and fees
payable or determined to be payable in connection with the execution and
delivery, filing or recording of this First Amendment and the other instruments
and documents to be delivered hereunder, and


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agrees to hold the Agent and each Lender harmless from and against any and all
liabilities with respect to or resulting from any delay in paying or omission to
pay such taxes or fees.

            SECTION 5. Governing Law. This First Amendment shall be governed by
and construed in accordance with the laws of the State of New York applicable to
agreements made and to be performed entirely within such State.

            SECTION 6. Headings. Section headings in this First Amendment are
included herein for convenience of reference only and shall not constitute a
part of this First Amendment for any other purpose.

            SECTION 7. Counterparts. The First Amendment may be executed by the
parties hereto in separate counterparts, each of which, when so executed and
delivered, shall be an original, but all such counterparts shall together
constitute one and the same instrument.

            IN WITNESS WHEREOF, the parties hereto have caused this First
Amendment to be executed by their respective officers thereunto duly authorized
as of the date first above written.


                                     THE NAVIGATORS GROUP, INC.,
                                      as Borrower

                                     By /s/ Bradley D. Wiley
                                        ----------------------------------
                                        Name: Bradley D. Wiley
                                        Title: Sr VP & CFO



                                     THE FIRST NATIONAL BANK OF CHICAGO,
                                     as Issuing Bank


                                     By
                                        ----------------------------------
                                        Name:
                                        Title:


                                     per pro BROWN BROTHERS HARRIMAN &
                                     CO., as Lender


                                     By
                                        ----------------------------------
                                        Name:


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