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                                                                    EXHIBIT 10.2

                               FIRST AMENDMENT TO
                     REVOLVING CREDIT AND SECURITY AGREEMENT

      This First Amendment to Revolving Credit and Security Agreement
("Amendment") is made as of the 4th day of October, 2001 by and among Bentley
Systems, Incorporated, a Delaware corporation ("Bentley"), Bentley Software,
Inc., a Delaware corporation ("Bentley Software"), and Atlantech Solutions,
Inc., a Delaware corporation ("Atlantech") (each an "Borrower" and collectively
"Borrowers"), the financial institutions which are now or which hereafter become
a party hereto (collectively, the "Lenders" and individually a "Lender") and PNC
Bank, National Association ("PNC"), as agent for Lenders (PNC, in such capacity,
the "Agent").

                                   BACKGROUND

      A. Borrowers, Agent and Lenders are parties to a certain Revolving Credit
and Security Agreement dated December 26, 2000 (as modified and amended from
time to time, the "Loan Agreement") pursuant to which Borrowers established
certain financing arrangements with Agent and Lenders. The Loan Agreement and
all instruments, documents and agreements executed in connection therewith or
related thereto are referred to herein collectively as the "Existing Loan
Documents". All capitalized terms not otherwise defined herein shall have the
meaning ascribed thereto in the Loan Agreement.

      B. Borrowers have requested and Lenders have agreed to amend the Agreement
subject to the terms and conditions of this Amendment.

      NOW, THEREFORE, with the foregoing Background incorporated by reference
and made a part hereof and intending to be legally bound, the parties agree as
follows:

      1. Amendment. The Loan Agreement is hereby amended and modified in the
following manner:

            (a) Foreign Non-Product Receivable. The following new definition is
added to Section 1.1 of the Loan Agreement:

            "Foreign Non-Product Receivable" shall mean a Receivable generated
            by a Borrower's rendition of maintenance services, and owing from a
            Customer located outside of the United States and the sale is on
            letter of credit, guaranty, credit insurance or acceptance terms, in
            each case acceptable to Agent in its sole but reasonable discretion.

            (b) Eligible Receivables. The definition of "Eligible Receivables"
contained in Section 1.1 of the Loan Agreement is hereby amended and restated in
its entirety as follows:

            "Eligible Receivables" shall mean and include with respect to each
            Borrower (or in the case of Foreign Product Receivables and Foreign
            Non-Product Receivables, a Subsidiary of a Borrower), each Domestic


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            Product Receivable, Domestic Non-Product Receivable, Foreign Product
            Receivable, or Foreign Non-Product Receivable of such Borrower or
            Subsidiary, as applicable, arising in the ordinary course of such
            Borrower's business and which Agent, in its sole but reasonable
            credit judgment in good faith, shall deem to be an Eligible
            Receivable, based on such considerations as Agent may from time to
            time deem appropriate. A Receivable shall not be deemed eligible
            unless such Receivable is subject to Agent's first priority
            perfected security interest (except with respect to Foreign Product
            Receivables and Foreign Non-Product Receivables) and no other Lien
            (other than Permitted Encumbrances), and is evidenced by an invoice
            or other documentary evidence satisfactory to Agent. In addition, no
            Receivable shall be an Eligible Receivable if:

                  (a) it arises out of a sale made by any Borrower to an
            Affiliate of any Borrower (except if such Person has executed a no
            offset agreement acceptable to Agent) or to a Person controlled by
            an Affiliate of any Borrower;

                  (b) if a Domestic Product Receivable, it is due or unpaid more
            than 120 days past the original invoice date or 90 days past the due
            date; if a Domestic Non-Product Receivable, it is due or unpaid more
            than 90 days past the original invoice date or 60 days past the due
            date; if a Foreign Product Receivable, it is due or unpaid more than
            the later of 90 days past the original invoice date or 180 days past
            the shipment date; if a Foreign Non-Product Receivable, is due or
            unpaid more than the later of 90 days past the original invoice date
            or 60 days past the due date;

                  (c) 50% or more of the Receivables from such Customer are not
            deemed Eligible Receivables hereunder;

                  (d) any covenant, representation or warranty contained in this
            Agreement with respect to such Receivable has been breached;

                  (e) the Customer shall (i) apply for, suffer, or consent to
            the appointment of, or the taking of possession by, a receiver,
            custodian, trustee or liquidator of itself or of all or a
            substantial part of its property or call a meeting of its creditors,
            (ii) admit in writing its inability, or be generally unable, to pay
            its debts as they become due or cease operations of its present
            business, (iii) make a general assignment for the benefit of
            creditors, (iv) commence a voluntary case under any state or federal
            bankruptcy laws (as now or hereafter in effect), (v) be adjudicated
            a bankrupt or insolvent, (vi) file a petition seeking to take
            advantage of any other law providing for the relief of debtors,
            (vii)


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            acquiesce to, or fail to have dismissed, any petition which is filed
            against it in any involuntary case under such bankruptcy laws, or
            (viii) take any action for the purpose of effecting any of the
            foregoing;

                  (f) with respect to Domestic Product Receivables, the sale is
            to a Customer that does not have a substantive presence or assets
            within the continental United States of America, unless the sale is
            on letter of credit, guaranty or acceptance terms, in each case
            acceptable to Agent in its sole but reasonable discretion;

                  (g) the sale to the Customer is on a bill-and-hold, guaranteed
            sale, sale-and-return, sale on approval, consignment or any other
            repurchase or return basis or is evidenced by chattel paper;

                  (h) Agent believes, in its sole but reasonable judgment, that
            collection of such Receivable is insecure or that such Receivable
            may not be paid by reason of the Customer's financial inability to
            pay;

                  (i) the Customer is the United States of America, any state or
            any department, agency or instrumentality of any of them, unless
            either (a) the Receivable owing from such Customer is less than
            $10,000 (or such lesser amount as determined by Agent in its sole
            discretion), or (b) the applicable Borrower assigns its right to
            payment of such Receivable to Agent pursuant to the Assignment of
            Claims Act of 1940, as amended (31 U.S.C. Sub-Section 3727 et seq.
            and 41 U.S.C. Sub-Section 15 et seq.) ("Claims Act") or has
            otherwise complied with other applicable statutes or ordinances;

                  (j) the goods giving rise to such Receivable have not been
            shipped to the Customer or, except with respect to Domestic
            Non-Product Receivables and Foreign Non-Product Receivables, the
            services giving rise to such Receivable have not been performed by
            the applicable Borrower or the Receivable otherwise does not
            represent a final sale;

                  (k) the Receivables of the Customer exceed a credit limit
            determined by Agent, in its sole but reasonable discretion, to the
            extent such Receivable exceeds such limit;

                  (l) the Receivable is subject to any offset, credit or
            deduction outside of the ordinary course of business to the extent
            of such offset, credit or deduction; or subject to a defense,
            dispute, or counterclaim; or the Customer is also a creditor or
            supplier of a Borrower (unless such Customer has executed a no
            offset agreement in form reasonably acceptable to Agent), to the
            extent of the contra; or


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            the Receivable is contingent in any respect or for any reason;

                  (m) the applicable Borrower has made any agreement with the
            Customer owing the Receivable for any deduction therefrom, except
            for discounts or allowances made in the ordinary course of business
            for prompt payment, all of which discounts or allowances are
            reflected in the calculation of the face value of each respective
            invoice related thereto;

                  (n) any return, rejection or repossession of the merchandise
            has occurred or the rendition of services has been disputed; or

                  (o) such Receivable is not otherwise satisfactory to Agent as
            determined in good faith by Agent in the exercise of its discretion
            in a reasonable manner.

      (c) Foreign Product Receivables. The definition of "Foreign Product
Receivable" contained in Section 1.1 of the Loan Agreement is hereby amended and
restated in its entirety as follows:

            "Foreign Product Receivable" shall mean a Receivable generated by a
            Borrower's or a Subsidiary's sale or license of software or services
            (other than maintenance services) or rendition of consulting or
            training services, and owing from a Customer located outside of the
            United States and the sale is on letter of credit, guaranty, credit
            insurance or acceptance terms, in each case acceptable to Agent in
            its sole but reasonable discretion.

      2. Effectiveness Conditions. This Amendment shall be effective upon the
satisfaction of the following conditions precedent (as determined in Agent's
sole discretion and all documents to be in form and substance satisfactory to
Agent and Agent's counsel):

            (a) Execution by Borrowers and Lenders and delivery to Agent of this
Amendment;

            (b) No Default or Event of Default shall have occurred under the
Existing Loan Documents; and

            (c) Such other documents, instruments and agreements which Agent
requests (in its sole and absolute discretion).

      3. Representations and Warranties. Each Borrower jointly and severally
represents and warrants to Agent and Lenders that:

            (a) All warranties and representations made to Agent and Lenders
under the Existing Loan Documents are true and correct as of the date hereof as
though made on the date


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hereof.

            (b) The execution and delivery by each Borrower of this Amendment
and the performance by each of them of the transactions herein contemplated (i)
are and will be within each Borrower's powers, (ii) have been authorized by all
necessary action and (iii) are not and will not be in contravention of any law,
any order of any court or other agency of government, or any other indenture,
agreement or undertaking to which any Borrower is a party or by which the
property of any Borrower is bound, or be in conflict with, result in a breach
of, or constitute (with due notice and/or lapse of time) a default under any
such indenture, agreement or undertaking or result in the imposition of any
lien, charge or encumbrance of any nature on any of the properties of any
Borrower.

            (c) This Amendment and any assignment, instrument, document, or
agreement executed and delivered in connection herewith, are the valid and
binding obligations of Borrowers and are enforceable against Borrowers in
accordance with their respective terms.

            (d) No Default or Event of Default has occurred under the Existing
Loan Documents.

      4. Collateral. As security for the timely payment of the Obligations and
satisfaction by Borrowers of all covenants and undertakings contained in the
Existing Loan Documents, each Borrower reconfirms the prior security interest
and a continuing first lien on and upon and to, its Collateral, whether now
owned or hereafter acquired, created or arising and wherever located. Borrowers
each hereby confirm and agree that all security interests and Liens granted to
Agent, for the benefit of Lenders, continue in full force and effect and shall
continue to secure the Obligations. All Collateral remains free and clear of any
Liens other than Permitted Encumbrances. Nothing herein contained is intended to
in any manner impair or limit the validity, priority and extent of Agent's
existing security interest in and Liens upon the Collateral.

      5. Ratification of Existing Loan Documents. Except as expressly set forth
herein, all of the terms and conditions of the Existing Loan Documents are
hereby ratified and confirmed and continue unchanged and in full force and
effect. All references to the Loan Agreement shall mean the Loan Agreement as
modified by this Amendment.

      6. Governing Law. This Amendment shall be governed by, construed and
enforced in accordance with the laws of the Commonwealth of Pennsylvania.

      7. Counterparts. This Amendment may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an original,
and such counterparts together shall constitute one and the same respective
agreement. Signature by facsimile shall bind the parties hereto.

      8. WAIVER OF JURY TRIAL. EACH BORROWERS, AGENT AND LENDERS WAIVE THE RIGHT
TO TRIAL BY JURY IN ANY ACTION, SUIT, PROCEEDING OR COUNTERCLAIM OF ANY KIND
ARISING OUT OF OR RELATED TO THIS AMENDMENT OR THE TRANSACTIONS DESCRIBED
HEREIN.


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      IN WITNESS WHEREOF, the parties have executed this Amendment as of the day
and year first above written.

BORROWERS:                               BENTLEY SYSTEMS, INCORPORATED

                                         By:    /s/ David Nation
                                                --------------------------------
                                         Name:  David Nation
                                                --------------------------------
                                         Title: Senior Vice President
                                                --------------------------------


                                         BENTLEY SOFTWARE, INC.

                                         By:    /s/ David Nation
                                                --------------------------------
                                         Name:  David Nation
                                                --------------------------------
                                         Title: Vice President
                                                --------------------------------


                                         ATLANTECH SOLUTIONS, INC.

                                         By:    /s/ David Nation
                                                --------------------------------
                                         Name:  David Nation
                                                --------------------------------
                                         Title: Vice President
                                                --------------------------------


AGENT:                                   PNC BANK, NATIONAL ASSOCIATION

                                         By:    /s/ Craig T. Sheetz
                                                --------------------------------
                                         Name:  Craig T. Sheetz
                                                --------------------------------
                                         Title: Vice President
                                                --------------------------------


LENDERS:                                 PNC BANK, NATIONAL ASSOCIATION

                                         By:    /s/ Craig T. Sheetz
                                                --------------------------------
                                         Name:  Craig T. Sheetz
                                                --------------------------------
                                         Title: Vice President
                                                --------------------------------


                                         CITICORP USA, INC.

                                         By:    /s/ Andrew J. Preston
                                                --------------------------------
                                         Name:  Andrew J. Preston
                                                --------------------------------
                                         Title: Vice - President
                                                --------------------------------


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