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                                                                   EXHIBIT 10.76

                                     FORM OF
                        INTEGRATED SECURITY SYSTEMS, INC.
                             SUBSCRIPTION AGREEMENT

Integrated Security Systems, Inc.
8200 Springwood Drive
Suite 230
Irving, Texas  75063

Gentlemen:

         This Subscription Agreement ("Agreement") has been executed by the
undersigned in connection with the private placement of up to 150,000 shares
(the "Shares") of Series D Convertible Preferred Stock, par value $0.01 per
share (the "Preferred Stock"), of Integrated Security Systems, Inc. (the
"Company"). The undersigned hereby makes the following representations,
warranties and agreements:

         1. INFORMATION. The undersigned has received and carefully reviewed the
Company's Confidential Offering Memorandum dated August 1999 (the "Offering
Memorandum"). The Company represents and warrants to the undersigned that from
the date of the Offering Memorandum to the date of acceptance of this Agreement
by the Company, the Offering Memorandum, as such may be supplemented or amended,
will not contain any untrue statement of a material fact or omit to state a
material fact in order to make the statements therein, in light of the
circumstances under which they were made, not misleading. The representations
and warranties herein contained shall survive the execution and delivery of this
Agreement and the sale of the Shares hereunder.

         2. AGREEMENT TO SUBSCRIBE. The undersigned hereby subscribes for
__________ Shares at a price of $20.00 per Share, payment for which in the
amount of $______________________ is made herewith. Payment for such
subscription is being made by check, bank draft or money order.

         The Company may accept or reject any subscription in whole or in part
or otherwise alter the terms under which subscriptions may be accepted. The
Company, its officers, directors, current shareholders and their affiliates may
purchase Shares on the same basis as other subscribers.

         The undersigned understands that except as provided under state
securities laws, this subscription is irrevocable and that the execution and
delivery of this Agreement will not constitute an agreement between the
undersigned and the Company until this Agreement has been accepted by the
Company. No subscription shall be deemed accepted until the subscription has
been accepted and, if necessary, any subsequent acts have been taken which shall
be deemed an acceptance of this Agreement by the Company.

         3. ACCESS TO INFORMATION. The undersigned acknowledges that the
undersigned is subscribing for the Shares after what the undersigned deems to be
adequate investigation of the business and prospects of the Company by the
undersigned. The undersigned has been furnished with the Offering Memorandum and
any other materials relating to the business and operation of the Company that
have been requested by him, her or it and has been given an opportunity to make
any further inquiries desired of the management and any other personnel of the
Company. The undersigned has received complete and satisfactory answers to any
such inquiries.


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         4. CERTAIN REPRESENTATIONS. The undersigned represents and warrants
that the information provided in the Accredited Investor Questionnaire submitted
herewith to the Company by or on behalf of the undersigned is true and correct
as of the date hereof. The representations, warranties, agreements, undertakings
and acknowledgments made by the undersigned in this Agreement are made with the
intent that they be relied upon by the Company in determining the undersigned's
suitability as a purchaser of the Shares, and shall survive its purchase. In
addition, the Investor undertakes to notify the Company immediately of any
change in any representation, warranty or other information relating to the
undersigned set forth herein.

                  (a) If the undersigned is a corporation, it is duly organized,
         validly existing and in good standing under the laws of the state and
         country of its incorporation; that the corporation has the corporate
         power to carry on its business and to make the investment contemplated
         herein and that this investment is for a proper corporate purpose; that
         this Agreement has been duly and validly authorized, executed and
         delivered and when accepted by the Company will constitute the valid,
         binding and enforceable agreement of the undersigned; that the
         corporation has not been organized solely for the purpose of acquiring
         the Shares; that the corporation has sufficient liquid assets to pay
         the full acquisition costs in connection with the Shares it proposes to
         acquire; and that the corporation has sufficient assets such that it
         can afford a total loss of its investment in the Shares.

                  (b) If the undersigned is a partnership or association, it has
         not been organized solely for the purpose of acquiring the Shares; that
         each individual partner of the partnership or member of the association
         can bear the economic risks of his, her or its pro rata share of this
         investment and can afford a total loss of his, her or its investment;
         and that each individual partner or member has sufficient liquid assets
         to pay his, her or its portion of the full acquisition costs in
         connection with the Shares the partnership or association has agreed to
         acquire, has adequate means of providing for his, her or its current
         needs and possible personal contingencies, and has no present need for
         liquidity of his, her or its investment.

                  (c) The undersigned has been advised that Offering of the
         Shares is not being registered under the Securities Act of 1933, as
         amended (the "Act"), on the basis of the exemption provided for in Rule
         506 of Regulation D thereof and on the representations made by the
         undersigned herein. The undersigned understands that no federal or
         state agency has passed on or made any recommendation or endorsement of
         the Shares and that the Company is relying on the truth and accuracy of
         the representations, declarations and warranties herein made by the
         undersigned in offering the Shares for sale to the undersigned without
         having first registered the same under the Act.

                  (d) The undersigned is acquiring the Shares for investment for
         the undersigned's own account and not with a view to their resale or
         distribution and does not intend to divide his, her or its
         participation with others or to resell or otherwise dispose of all or
         any part of the Shares unless and until they are subsequently
         registered under the Act, or an exemption from such registration is
         available.

                  (e) The undersigned has the ability to evaluate the merits and
         risks of an investment in the Company based upon his, her or its
         knowledge and experience in financial and business matters.


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                  (f) The undersigned understands that, in the view of the
         Securities and Exchange Commission (the "Commission"), the statutory
         exemption referred to above would not be available if, notwithstanding
         the undersigned's representations, the undersigned has in mind merely
         acquiring the Shares for immediate resale or distribution upon a market
         developing therefor.

                  (g) The undersigned further understands that in the event Rule
         144 under the Securities Act ("Rule 144") hereafter becomes applicable
         to the Shares, any routine sale of the Shares made thereunder can be
         made only in limited amounts in accordance with the terms and
         conditions of this Agreement and of Rule 144 and that in the event Rule
         144 is not applicable, compliance with a disclosure exemption will be
         required before the undersigned can transfer part or all of the Shares.

                  (h) The undersigned accepts the condition that before any
         transfer of any of the Shares can be made by the undersigned, written
         approval must first be obtained from the Company's counsel. The basis
         of such approval shall be in compliance with the requirements of the
         federal and state statutes regulating securities. The undersigned
         understands that a legend to this effect will be placed on the Shares
         and that stop-transfer instructions will be issued by the Company to
         its transfer agent.

                  (i) The undersigned understands and agrees that if the
         undersigned's subscription is accepted, the undersigned may be required
         to execute other documents to effectuate or evidence his, her or its
         purchase of the Shares.

                  (j) No one acting on behalf of the Company has made any
         representation, warranty, or agreement to or with the undersigned with
         respect to purchase of the Shares, except as described herein and in
         the Offering Memorandum.

                  (k) The undersigned's investment in the Company has not been
         solicited by means of public solicitation or advertisement and all of
         the information and representations contained herein, particularly
         those representations relating to the undersigned's general ability to
         bear the risks of the investment being made hereby and the
         undersigned's suitability as an investor, are true and correct.

                  (l) The undersigned is aware that the Shares are a speculative
         investment involving a very high degree of risk and that there is no
         guarantee that the undersigned will realize any gain from the
         undersigned's investment. The undersigned is (i) able to bear the
         economic risk of this investment, (ii) able to hold the Shares
         indefinitely, and (iii) presently able to afford a complete loss of
         this investment. The undersigned has consulted the undersigned's own
         attorney, accountant or investment advisor with respect to the
         undersigned's investment in the Shares and its suitability for the
         undersigned.

                  (m) The undersigned has adequate other means of providing for
         the undersigned's current needs and personal contingencies and therefor
         has no need for liquidity in this investment. The undersigned's overall
         commitment to investments that are not readily marketable is not
         disproportionate to the undersigned's net worth and the undersigned's
         investment in the Shares will not cause such overall commitment to
         become excessive.


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                  (n) The undersigned represents that the funds provided for
         this investment are either separate property of the undersigned,
         community property over which the undersigned has the right of control
         or are otherwise funds as to which the undersigned has the right of
         management.

                  (o) The undersigned understands the meaning and legal
         consequences of the representations and warranties made herein, all of
         which are true and correct as of the date hereof and will be true and
         correct as of the date of the undersigned's acquisition of the Shares
         subscribed for herein. Each such representation and warranty shall
         survive such purchase.

                  (p) The undersigned is a bona fide resident of the state set
         forth on the signature page hereof, maintains his, her or its principal
         residence there and is at least 21 years of age.

                  (q) The undersigned has relied on his, her or its own legal
         counsel to the extent the undersigned has deemed necessary as to all
         legal matters and questions presented with reference to the offering
         and sale of the Shares subscribed for herein.

                  (r) The undersigned hereby agrees that this subscription is
         irrevocable and that the representations and warranties set forth in
         this Agreement shall survive the acceptance hereof by the Company.

                  (s) The undersigned hereby agrees and acknowledges that the
         agreements and representations herein set forth shall become effective
         and binding upon the undersigned and the undersigned's heirs, legal
         representatives, successors and assigns upon the Company's acceptance
         hereof.

                  (t) The undersigned is an accredited investor as defined in
         Rule 501 of Regulation D under the Act.

                  (u) (For Residents of All States). The undersigned understands
         and agrees to the following:

                           IN MAKING AN INVESTMENT DECISION, INVESTORS MUST RELY
                  ON THEIR OWN EXAMINATION OF THE COMPANY AND THE TERMS OF THE
                  OFFERING, INCLUDING THE MERITS AND RISKS INVOLVED. THESE
                  SECURITIES HAVE NOT BEEN RECOMMENDED BY ANY FEDERAL OR STATE
                  SECURITIES COMMISSION OR REGULATORY AUTHORITY. FURTHERMORE,
                  THE FOREGOING AUTHORITIES HAVE NOT CONFIRMED THE ACCURACY OR
                  DETERMINED THE ADEQUACY OF THIS DOCUMENT. ANY REPRESENTATION
                  TO THE CONTRARY IS A CRIMINAL OFFENSE.

                           THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON
                  TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR
                  RESOLD EXCEPT AS PERMITTED UNDER THE SECURITIES ACT OF 1933,
                  AS AMENDED, AND APPLICABLE STATE SECURITIES LAWS, PURSUANT TO
                  REGISTRATION OR EXEMPTION THEREFROM. INVESTORS SHOULD BE AWARE
                  THAT THEY MAY BE REQUIRED TO BEAR THE FINANCIAL RISKS OF THIS
                  INVESTMENT FOR AN INDEFINITE PERIOD OF TIME.

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                  (v) (For New York Residents Only). The undersigned understands
         and agrees to the following:

                           THE COMPANY'S PRIVATE OFFERING MEMORANDUM HAS NOT
                  BEEN REVIEWED BY THE ATTORNEY GENERAL OF THE STATE OF NEW YORK
                  PRIOR TO ITS ISSUANCE AND USE. THE ATTORNEY GENERAL OF THE
                  STATE OF NEW YORK HAS NOT PASSED ON OR ENDORSED THE MERITS OF
                  THIS OFFERING. ANY REPRESENTATION TO THE CONTRARY IS UNLAWFUL.

                  (w) (For Texas Residents Only). The undersigned understands
         and agrees to the following:

                           THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE
                  TEXAS SECURITIES ACT AND, IF OFFERED IN TEXAS OR TO TEXAS
                  RESIDENTS, ARE BEING SOLD IN RELIANCE UPON THE EXEMPTION
                  CONTAINED IN SECTION 5 OF SUCH ACT. THEY CANNOT BE RESOLD
                  UNLESS THEY ARE REGISTERED UNDER THE ACT OR UNLESS AN
                  EXEMPTION FROM REGISTRATION IS AVAILABLE.

         5. INDEMNIFICATION. The undersigned recognizes that the offer of the
Shares was made in reliance upon the undersigned's representations, warranties
and the acknowledgments and agreements set forth above. The undersigned agrees
to provide, if requested, any additional information that may reasonably be
required to determine the eligibility of the undersigned to purchase the Shares.
The undersigned hereby agrees to indemnify the Company and its affiliates and
controlling persons and to hold each of them harmless from and against any loss,
damage or liability due to or arising out of a breach of any representation,
warranty or agreement of the undersigned contained in this Agreement or in any
other document provided by the undersigned to the Company in connection with the
undersigned's investment in the Shares. The undersigned hereby agrees to
indemnify the Company and its affiliates and controlling persons and to hold
them harmless against all liabilities, costs or expenses (including reasonable
attorneys' fees) arising as a result of the sale or distribution of the Shares
by the undersigned in violation of the Securities Act or other applicable law or
any misrepresentation or breach by the undersigned with respect to the matters
set forth herein. In addition, the undersigned agrees to indemnify the Company
and its affiliates and controlling persons and to hold them harmless from and
against, any and all loss, damage, liability or expense, including costs and
reasonable attorneys' fees, to which they may be put or which they may incur or
sustain by reason of or in connection with any representation made by the
undersigned with respect to the matters about which representations or
warranties are required by the terms of this Agreement, or any breach of any
such warranties or any failure to fulfill any covenants or agreements set forth
herein or included in and as defined in the Offering Memorandum. Notwithstanding
any provision of this Agreement, the undersigned does not waive any rights
granted to it under applicable securities laws.

         6. GENERAL.

                  (a) All notices or other communications given or made
         hereunder shall be in writing and shall be delivered or mailed by
         registered or certified mail, return receipt requested, postage
         prepaid, to the undersigned at the undersigned's address set forth
         below and to the Company at the address set forth above.


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                  (b) Notwithstanding the place where this Agreement may be
         executed by any of the parties hereto, the parties expressly agree that
         all the terms and provisions hereof shall be construed in accordance
         with and governed by the internal laws of the State of Texas, without
         giving effect to conflicts of law.

                  (c) This Agreement constitutes the entire Agreement between
         the parties hereto with respect to the subject matter hereof and may be
         amended only by a writing executed by all parties. The undersigned
         agrees not to transfer or assign this Agreement, or any of his, her or
         its interest herein, without the express written consent of the
         Company.

                  (d) The undersigned agrees that counsel to the Company shall
         not be liable for taking any action pursuant to this Agreement in the
         absence of gross negligence, misfeasance, malfeasance or fraud.

                  (e) The undersigned has enclosed with this Agreement
         appropriate evidence of the authority of the individual executing this
         Agreement to act on its behalf (i.e., if a trust, a copy of the trust
         agreement; if a corporation, certified corporate resolution authorizing
         the signature and a copy of the articles of incorporation; or if a
         partnership, a copy of the partnership agreement).

                  Kindly deliver the certificates for the Shares registered as
follows:


                -------------------------------------------------
                                     (Name)

                -------------------------------------------------
                                (Street and No.)

                -------------------------------------------------
                           (City, State and Zip Code)

                -------------------------------------------------
                (Social Security No. or Federal Employer ID No.)

                -------------------------------------------------
                                 (Date of Birth)


                                         Very truly yours,


                                         ---------------------------------------
                                         (Signature of Subscriber)

Dated:                    , 1999
      --------------------
ACCEPTED AND AGREED:
INTEGRATED SECURITY SYSTEMS, INC.

By:
    ---------------------------------
    Gerald K. Beckmann, President and CEO