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                                                                    EXHIBIT 10.2

         THIS AMENDING AGREEMENT is made this 24th day of July, 2000 between
Hydrogenics Corporation (the "Corporation"), CIBC Capital Partners ("CIBC"),
Micro-Generation Technology Fund, L.L.C. ("MG Fund"), Working Ventures Canadian
Fund Inc. ("WV"), Reliant Energy Ventures Inc. (formerly Development Ventures
Inc.) ("DVI"), Pierre Rivard ("Rivard"), Joe Cargnelli ("Cargnelli") and Boyd
Taylor ("Taylor") (the Corporation, CIBC, MG Fund, WV, DVI, Rivard, Cargnelli
and Taylor collectively referred to herein as the "Parties" and each of them a
"Party").

RECITALS:

A.       The Parties, together with the Legacy Investors and other persons who
         become Shareholders from time to time, are all of the parties to the
         Amended and Restated Unanimous Shareholder's Agreement dated January
         24, 2000 (the "Shareholder's Agreement").

B.       The Parties consider it appropriate to amend the Shareholder's
         Agreement to amend matters relating to the size, composition and
         election of the Board and various committees appointed by the Board.

C.       Section 1.8 of the Shareholder's Agreement provides that the
         Shareholder's Agreement may be amended if such amendments are approved
         in writing by each of the Parties and any amendment so approved shall
         be binding on all Shareholders including the Legacy Investors and other
         persons who become Shareholders from time to time.

THEREFORE, the Parties agree as follows:

                                    ARTICLE 1
                                   DEFINITIONS

1.1      In this Amending Agreement all capitalized terms used herein (including
         without limitation, the recitals hereto) and not otherwise defined
         shall have the meanings ascribed to them in the Shareholder's
         Agreement.

                                    ARTICLE 2
                           DIRECTORS AND SHAREHOLDERS

2.1      NUMBER OF DIRECTORS

         Section 5.1 of the Agreement is hereby deleted in its entirety and
replaced with the following:

                  "5.1 Number of Directors. The Corporation's articles shall
                  provide for a minimum of three (3) and a maximum of nine (9)
                  Directors.
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                  The Corporation shall initially have seven (7) Directors who
                  shall be nominated and elected as provided for in Section
                  5.2."



2.2      MEMBERS OF THE BOARD OF DIRECTORS

         Section 5.2(a) of the Shareholder's Agreement is hereby deleted in its
         entirety and replaced with the following:

                  "(a) Nomination. The Board of Directors shall consist of one
                  nominee of WV, one nominee of CIBC, three nominees of Rivard,
                  Cargnelli and Taylor (acting together) and two other
                  Independent Directors, one of whom shall also act as chairman,
                  mutually acceptable to all parties. In the event that any of
                  Rivard, Cargnelli and Taylor are nominated to the Board, and
                  in the event of the death of any of them, the Shareholders
                  shall nominate a person who is Independent in the deceased's
                  place as Director. CIBC shall initially nominate as its
                  nominee an individual that will qualify as an Independent
                  Director."



2.3      OBSERVER STATUS FOR CIBC

         Immediately after Section 5.2(f) of the Shareholder's Agreement
         entitled "Observer Status for DVI", a new Section 5.2(g) shall be added
         as follows:

                  "(g) Observer Status for CIBC. In the event that CIBC has
                  nominated an individual that qualifies as an Independent
                  Director and for so long as CIBC is a Shareholder, CIBC shall
                  be entitled to receive notice of all meetings of the Board and
                  shall be invited to attend all such meetings but shall have no
                  voting or other rights thereat. The representative of CIBC
                  shall be entitled to compensation for reasonable travel and
                  out-of-pocket expenses incurred in attending such meetings,
                  upon presentation of receipts therefor."



2.4      OBSERVER STATUS FOR WV

         Immediately after the new Section 5.2(g) of the Shareholder's Agreement
         entitled "Observer Status for CIBC", a new Section 5.2(h) shall be
         added as follows:

                  "(h) Observer Status for WV. In the event that WV has
                  nominated an individual that qualifies as an Independent
                  Director and for so long as WV is a Shareholder, WV shall be
                  entitled to receive
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                  notice of all meetings of the Board and shall be invited to
                  attend all such meetings but shall have no voting or other
                  rights thereat. The representative of WV shall be entitled to
                  compensation for reasonable travel and out-of-pocket expenses
                  incurred in attending such meetings, upon presentation of
                  receipts therefor."



2.5      INSURANCE

         Section 5.5 of the Shareholder's Agreement is hereby deleted in its
         entirety and replaced with the following:

                  "5.5 Insurance. The Corporation shall arrange director's
                  insurance coverage for the Directors of the Corporation on
                  terms and conditions in an amount acceptable to the Board."



2.6      EXERCISE OF AUTHORITY - MANAGEMENT DEVELOPMENT AND COMPENSATION
         COMMITTEE

         Section 5.7(f) of the Shareholder's Agreement is hereby deleted in its
         entirety and replaced with the following:

                  "(f) Management Development and Compensation Committee. The
                  Board shall appoint a Management Development and Compensation
                  Committee and shall delegate to the Management Development and
                  Compensation Committee responsibility for the following: (i)
                  reviewing and recommending the terms of compensation packages
                  provided to the Corporation's employees including its
                  executive officers, (ii) reviewing and recommending the terms
                  of any bonus or other awards provided to the Corporation's
                  employees including its executive officers, (iii) reviewing
                  and recommending new executive officer appointees and (iv)
                  administering the Corporation's stock option plan. The
                  Management Development and Compensation Committee shall be
                  comprised solely of Directors and shall consist of at least
                  three members, one of whom shall be a nominee of CIBC and one
                  of whom shall be a nominee of WV. No more than one member of
                  the Senior Management Group shall be a member of the
                  Management Development and Compensation Committee. In order to
                  be effective, all decisions of the Management Development and
                  Compensation Committee shall be made by a unanimous vote of
                  its members at a meeting or in writing."
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2.7      EXERCISE OF AUTHORITY - AUDIT COMMITTEE

         Section 5.7(g) of the Shareholder's Agreement is hereby deleted in its
         entirety and replaced with the following:

                  "(g) Audit Committee. The Board shall appoint an Audit
                  Committee and shall delegate to the Audit Committee
                  responsibility for the following: (i) overseeing the
                  retention, performance and compensation of the Corporation's
                  independent auditors, and (ii) establishing procedures and
                  overseeing the Corporation's system of internal accounting and
                  auditing control. The Audit Committee shall be comprised
                  solely of Directors and shall consist of at least three
                  members, one of whom shall be a nominee of CIBC and one of
                  whom shall be a nominee of WV. No member of the Senior
                  Management Group shall be a member of the Audit Committee. In
                  order to be effective, all decisions of the Audit Committee
                  shall be made by a unanimous vote of its members at a meeting
                  or in writing."



2.8      EXERCISE OF AUTHORITY - NOMINATION AND CORPORATE GOVERNANCE COMMITTEE

         Immediately after Section 5.7(g) of the Shareholder's Agreement
         entitled "Audit Committee", a new Section 5.7(h) shall be added as
         follows:

                  "(h) Nomination and Corporate Governance Committee. The Board
                  shall appoint a Nomination and Corporate Governance Committee
                  and shall delegate to the Nomination and Corporate Governance
                  Committee responsibility for the following: (i) evaluating and
                  assessing the effectiveness of the Board, its Directors and
                  its various Committees, (ii) establishing procedures for
                  identifying new nominees to the Board, (iii) recruiting and
                  recommending new nominees to be elected to the Board, and,
                  (iv) developing and monitoring the Corporation's approach to
                  corporate governance issues. The Nomination and Corporate
                  Governance Committee shall be comprised solely of Directors
                  and shall consist of at least three members, one of whom shall
                  be a nominee of CIBC and one of whom shall be a nominee of WV.
                  No more than one member of the Senior Management Group shall
                  be a member of the Nomination and Corporate Governance
                  Committee. In order to be effective, all decisions of the
                  Nomination and Corporate Governance Committee shall be made by
                  a unanimous vote of its members at a meeting or in writing."
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                                    ARTICLE 3
                      ALL OTHER PROVISIONS REMAIN THE SAME

3.1      All other provisions contained in the Shareholder's Agreement and not
         explicitly amended as provided for herein remain the same and are
         hereby agreed to be in full force and effect.

3.2      For greater certainty and without limiting the generality of the
         foregoing, this Amending Agreement shall terminate at the same time and
         in the same manner as the Shareholder's Agreement terminates as is
         provided for in Section 2.1 thereof.



                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]
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IN WITNESS OF WHICH the Parties have duly executed this Amending Agreement on
the date first written above.



                     HYDROGENICS CORPORATION
                       By:  /s/PIERRE RIVARD
                            ---------------------------------------------------
                            Pierre Rivard
                            President


                     CIBC CAPITAL PARTNERS
                       By:  /s/TEDDY ROSENBERG
                            ---------------------------------------------------
                            Teddy Rosenberg
                            Managing Director




                     MICRO-GENERATION TECHNOLOGY FUND, L.L.C.

                     BY:  ARETE CORPORATION, MANAGER



                     By:    /s/ROBERT W. SHAW, JR.
                            ---------------------------------------------------
                            Robert W. Shaw, Jr.
                            President


                     WORKING VENTURES CANADIAN FUND INC.
                     By:    /s/BRIAN CARWANA
                            ---------------------------------------------------
                            Brian Carwana
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                     RELIANT ENERGY VENTURES, INC. (FORMERLY DEVELOPMENT
                     VENTURES, INC.)

                       By:  /s/THOMAS S. GLANVILLE
                            ---------------------------------------------------
                            Thomas S. Glanville
                            President


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<S>                                                                <C>
SIGNED, SEALED & DELIVERED
In the presence of:

                                                                                    /s/PIERRE RIVARD
-----------------------------------------------------              ---------------------------------------------------
                      Witness                                                        Pierre Rivard


SIGNED, SEALED & DELIVERED In the presence of:

                                                                                    /s/JOE CARGNELLI
-----------------------------------------------------              ---------------------------------------------------
                      Witness                                                        Joe Cargnelli


SIGNED, SEALED & DELIVERED In the presence of:

                                                                                     /s/BOYD TAYLOR
-----------------------------------------------------              ---------------------------------------------------
                      Witness                                                         Boyd Taylor
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