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                                                                     EXHIBIT 4.6


                           BORROWER SECURITY AGREEMENT


This SECURITY AGREEMENT (this "Agreement"), dated as of September 27, 2001, is
entered into among INTEGRATED SECURITY SYSTEMS, INC., a Delaware corporation
("Borrower"), RENAISSANCE US GROWTH & INCOME TRUST PLC ("RUSGIT"), RENAISSANCE
CAPITAL GROWTH & INCOME FUND III, INC., a Texas corporation ("Renaissance III")
(RUSGIT and Renaissance III collectively referred to as "Lender"), and
RENAISSANCE CAPITAL GROUP, INC., a Texas corporation, as agent for the Lender
(the "Agent").

                                    RECITALS

         A. Secured Party has lent to Pledgor the aggregate principal amount of
One Hundred Fifty Thousand Dollars ($150,000) evidenced by the Pledgor's
promissory notes of even date herewith (the "Notes").

         B. As a condition for the loan, Lender required that Borrower grant a
security interest in all of its assets as collateral for the loan and any other
indebtedness of Borrower to Lender (the "Obligations").

         NOW, THEREFORE, in consideration of the foregoing recitals and the
mutual covenants and agreements set forth herein, the parties agree as follows:

         1. Grant of Security Interest.

            (a) In order to secure payment when due of the Obligations now
existing or hereafter incurred, Borrower hereby irrevocably grants to the Lender
a first and prior security interest in the following property of the Borrower
(the "Collateral"), whether now owned or existing, or hereafter acquired, owned,
existing or arising (whether by contract or operation of law), and wherever
located, which shall be retained by Lender, until the Obligations have been paid
in full and the Loan Agreement has been terminated.

            (b) Collateral shall include all personal property of the Borrower,
including the following, all whether now owned or hereafter acquired or arising
and wherever located: (i) accounts (including health-care-insurance receivables
and credit card receivables); (ii) securities entitlements, securities accounts,
commodity accounts, commodity contracts and investment property; (iii) deposit
accounts [i-iii collectively referred to as "Accounts"]; (iv) instruments
(including promissory notes); (v) documents (including warehouse receipts); (vi)
chattel paper (including electronic chattel paper and tangible chattel paper);
(vii) inventory, including raw materials, work in process, or materials used or
consumed in Borrower's business, items held for sale or lease or furnished or to
be furnished under contracts of service, sale or lease, goods that are returned,
reclaimed or repossessed; (viii) goods of every nature, including
stock-in-trade, goods on consignment, standing timber that is to be cut and
removed under a conveyance or contract for sale, the unborn young of animals,
crops grown, growing, or to be grown,


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manufactured homes, computer programs embedded in such goods and farm products;
(ix) equipment, including machinery, vehicles and furniture; (x) fixtures; (xi)
agricultural liens; (xii) as-extracted collateral; (xiii) commercial tort
claims, if any, described on Exhibit "A" hereto; (xiv) letter of credit rights;
(xv) general intangibles, of every kind and description, including payment
intangibles, software, computer information, source codes, object codes, records
and data, all existing and future customer lists, choses in action, claims
(including claims for indemnification or breach of warranty), books, records,
patents and patent applications, copyrights, trademarks, tradenames,
tradestyles, trademark applications, goodwill, blueprints, drawings, designs and
plans, trade secrets, contracts, licenses, license agreements, formulae, tax and
any other types of refunds, returned and unearned insurance premiums, rights and
claims under insurance policies; (xvi) all supporting obligations of all of the
foregoing property; (xvii) all property of the Borrower now or hereafter in the
Lender's possession or in transit to or from, or under the custody or control
of, the Lender or any affiliate thereof; (xviii) all cash and cash equivalents
thereof; and (xix) all cash and noncash proceeds (including insurance proceeds)
of all of the foregoing property, all products thereof and all additions and
accessions thereto, substitutions therefor and replacements thereof. The
Collateral shall also include any and all other tangible or intangible property
that is described as being part of the Collateral pursuant to one or more Riders
to Security Agreement that may be attached hereto or delivered in connection
herewith, including the Rider to Security Agreement - Copyrights, the Rider to
Security Agreement - Patents, the Rider to Security Agreement - Trademarks and
the Rider to Security Agreement - Cash Collateral Account.

            (c) Borrower represents that the grant of security interest herein
is a first and prior security interest.

         2. Insurance on Collateral. Borrower further warrants and agrees that
it will pay for and maintain insurance in the amounts and of the types required
pursuant to Section 5.12 of the Loan Agreement.

         3. Covenant For Accounts.

            (a) The Borrower will, on the Lender's demand, make notations on its
books and records showing the Lender's security interest and make available to
the Lender shipping and delivery receipts evidencing the shipment of the goods
that gave rise to an account, completion certificates or other proof of the
satisfactory performance of services that gave rise to an account, a copy of the
invoice for each account and copies of any written contract or order from which
an account arose. The Borrower shall promptly notify the Lender if an account
becomes evidenced or secured by an instrument or chattel paper and upon the
Lender's request, will promptly deliver any such instrument or chattel paper to
the Lender, including any letter of credit delivered to the Borrower to support
a shipment of inventory by the Borrower.

            (b) The Borrower will promptly advise the Lender whenever an account
debtor refuses to retain or returns any goods from the sale of which an account
arose and will comply with any instructions that the Lender may give regarding
the sale or other disposition of such returns. From time to time with such
frequency as the Lender may request, the Borrower will report to the Lender all
credits given to account debtors on all accounts.


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            (c) The Borrower will immediately notify the Lender if any account
arises out of contracts with the United States or any department, agency or
instrumentality thereof, and will execute any instruments and take any steps
required by the Lender so that all monies due and to become due under such
contract shall be assigned to the Lender and notice of the assignment given to
and acknowledged by the appropriate government agency or authority under the
Federal Assignment of Claims Act.

            (d) At any time after the occurrence of a Default, and without
notice to the Borrower, the Lender may direct any persons who are indebted to
the Borrower on any Collateral consisting of accounts or general intangibles to
make payment directly to the Lender of the amounts due. The Lender is authorized
to collect, compromise, endorse and sell any such Collateral in its own name or
in the Borrower's name and to give receipts to such account debtors for any such
payments and the account debtors will be protected in making such payments to
the Lender. Upon the Lender's written request, the Borrower will establish with
the Lender and maintain a lockbox account ("Lockbox") with the Lender and a
depository account(s) ("Cash Collateral Account") with the Lender subject to the
provisions of this subparagraph and such other related agreements as the Lender
may require, and the Borrower shall notify its account debtors to remit payments
directly to the Lockbox. Thereafter, funds collected in the Lockbox shall be
transferred to the Cash Collateral Account, and funds in the Cash Collateral
Account shall be applied by the Lender, daily, to reduce the outstanding
Obligations.

            (e) Upon Agent's request, upon the occurrence and during the
continuance of a Default, Borrower will, at any reasonable time and at
Borrower's own expense, physically deliver to Agent, all Accounts (including
inter-company receivables) assigned to Agent at any reasonable place or places
designated by Agent. Failure to deliver any Account, or failure to deliver
physical possession of any instruments, documents or writings in respect of any
Account shall not invalidate Agent's Lien and security interest therein, except
to the extent that possession may be required by applicable law for the
perfection of said Lien or security interest, in which latter case, the Account
shall be deemed to be held by the Borrower as the custodian agent of Agent, for
the benefit of Lender. Failure of Agent to demand or require Borrower to include
any Account in any schedule, to execute any schedule, to assign and deliver any
schedule or to deliver physical possession of any instruments, documents or
writings related to any Account shall not relieve Borrower of its duty so to do.

            (f) Borrower hereby agrees that it shall use commercially reasonable
efforts, at its sole cost and expense and in its own name, to promptly and
diligently collect and enforce payment of all Accounts and Borrower will defend
and hold Lender and Agent harmless from any and all loss, damage, penalty, fine
or expense arising from such collection or enforcement.

         4. Financing Statements. Borrower agrees to execute all financing
statements and amendments thereto as Agent, on behalf of the Lender, may request
from time to time to evidence the security interest granted to Agent hereunder
and will pay the cost of all filing fees and taxes, if any, necessary to effect
the filing thereof. By its signature hereon, the Borrower hereby irrevocably
authorizes the Lender to execute (on behalf of the Borrower) and file against
the Borrower one or more financing, continuation or amendment statements
pursuant to the Uniform Commercial Code in form satisfactory to the Lender, and
the Borrower will pay the cost of


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preparing and filing the same in all jurisdictions in which such filing is
deemed by the Lender to be necessary or desirable in order to perfect, preserve
and protect its security interests. Without the written consent of Agent,
Borrower will not allow any financing statement or notice of assignment to be on
file in any public office covering any Collateral, proceeds thereof or other
matters subject to the security interest granted to Agent herein, unless such
financing statement relates to a Permitted Lien.

         5. Software as Collateral. As part of the Collateral, Borrower has
delivered to Lender certain computer software, drivers and documentation
therefor, including all source and object code versions thereof (in electronic
and hard copies) and all enhancements and developments relating thereto (the
foregoing are collectively referred to herein as "Software"). Borrower grants to
Lender access and use to the Software. Borrower will update the Software in
possession of Lender no more than six (6) times per year, but no less often than
each major revision to the Software. Should Borrower default in the payment of
the Obligations, then Borrower hereby grants Lender a perpetual, nonexclusive,
royalty-free license to copy, make derivative works, and use the Software for
all of its business purposes (the "License"), as well as title and ownership to
the Software. Upon satisfaction of the Obligation by Borrower, Lender shall
promptly return the Software to Borrower and shall have no further rights to
access of use thereof. Lender acknowledges that third party software may be
required to use the Software, and it is Lender's responsibility to obtain any
rights to use such third party software. Nothing herein will grant to Lender any
title or ownership interest in the Software. To the extent that Lender modifies,
updates, or enhances the Software ("Enhancements"), Lender shall own the same.
Borrower hereby represents and warrants to Lender that Borrower has full right,
title and interest in and to the Software, the Software is complete and will
function in accordance with the documentation therefor, and the use of the
Software will not infringe any third party intellectual property or other
rights.

         6. Lender's Payment of Claims. Lender may, in its sole discretion,
discharge or obtain the release of any Lien asserted by any Person against the
Collateral, other than a Permitted Lien which, in the Lender's judgment, may
have a Material Adverse Effect on the Lender's rights with respect to the
Collateral. All sums paid by Lender in respect thereof shall be payable, on
demand, by Borrower to Lender and shall be a part of the Obligations.

         7. Default and Remedies.

            (a) Borrower shall be in default in the full and prompt payment,
when due, of the Obligations (a "Default").

            (b) Upon the occurrence and during the continuation of any Default
(i) unless Lender or Agent shall elect otherwise, the entire unpaid amount of
the Obligations due under the Loan Agreement, as are not then otherwise due and
payable, shall become immediately due and payable without notice to Borrower or
demand by Lender or Agent and (ii) either Lender or Agent may, at its or their
option, exercise from time to time any and all rights and remedies available to
them under the Uniform Commercial Code or otherwise, including the right to
foreclose or otherwise realize upon the Collateral and to dispose of any of the
Collateral at one or more public or private sales or other proceedings, and
Borrower agrees that any of Lender, Agent


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or their nominee may become the purchaser at any such sale or sales. Borrower
agrees that twenty (20) days shall be reasonable prior notice of the date of any
public sale or other disposition of the same. All rights and remedies granted
Lender hereunder or under any other agreement between Lender and Borrower shall
be deemed concurrent and cumulative and not alternative, and Lender, or Agent on
its behalf, may proceed with any number of remedies at the same time or at
different times until all the Obligations are fully satisfied. The exercise of
any one right or remedy shall not be deemed a waiver or release of, or an
election against, any other right or remedy. Borrower shall pay to Lender or
Agent, on demand, any and all expenses (including reasonable attorneys' fees and
legal expenses) which may have been incurred by Lender or Agent (i) in the
prosecution or defense of any action arising under this Agreement, the
Collateral or any of Lender's rights therein or thereto; or (ii) in connection
with the custody, preservation, use, operation, preparation for sale or sale of
the Collateral, the incurring of all of which are hereby authorized to the
extent Lender or Agent deem the same advisable. Borrower's liability to Lender
or Agent for any such payment shall be included in the Obligations. The proceeds
of any Collateral received by Lender or Agent at any time before or after a
Default, whether from a sale or other disposition of Collateral or otherwise, or
the Collateral itself, may be applied to the payment, in full or in part, of
such of the Obligations and in such order and manner as Lender or Agent may
elect.

         8. Representations and Covenants of Borrower. Borrower hereby
represents to and agrees with Lender as follows:

            (a) Borrower owns the Collateral as sole owner, free and clear of
any Liens, other than Permitted Liens.

            (b) So long as any Obligations remain unpaid, Borrower agrees not to
sell, assign or transfer the Collateral, other than sales of Collateral in the
ordinary course of business, and to maintain it free and clear of any Liens,
other than Permitted Liens.

         9. Miscellaneous.

            (a) This Agreement shall bind and inure to the benefit of the
parties and their respective heirs, personal representatives, successors and
assigns, except that Borrower shall not assign any of its rights hereunder
without the prior written consent of holders of more than 50% of the principal
amount of the then outstanding Debentures.

            (b) Any provision hereof which is prohibited or unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability without affecting the validity or
enforceability of the remainder of this Agreement or the validity or
enforceability of such provision in any other jurisdiction.

            (c) This Agreement shall be governed by and construed and enforced
in accordance with the substantive laws of the State of Texas, without regard to
the conflicts of laws provisions thereof, and the applicable laws of the United
States. Venue and jurisdiction shall be in the state or federal courts in Dallas
County, Texas.


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            (d) Borrower hereby consents to the jurisdiction of the courts of
the State of Texas in any action or proceeding which may be brought against it
under or in connection with this Agreement or any transaction contemplated
hereby or to enforce any agreement contained herein and, in the event any such
action or proceeding shall be brought against it, Borrower agrees not to raise
any objection to such jurisdiction or to the laying of venue in Dallas County,
Texas or, if applicable, any other county in any state in which Collateral is
located.

            (e) All capitalized terms, unless otherwise specified, have the
meanings assigned to them in the Loan Agreement and the Debentures.

            (f) Any notices or other communications required or permitted to be
given by this Agreement or any other documents and instruments referred to
herein must be (i) given in writing and personally delivered, mailed by prepaid
certified or registered mail or sent by overnight service, such as FedEx, or
(ii) made by telex or facsimile transmission delivered or transmitted to the
party to whom such notice or communication is directed, with confirmation
thereupon given in writing and personally delivered or mailed by prepaid
certified or registered mail.

       If to Borrower to:


                  Integrated Security Systems, Inc.
                  8200 Springwood Drive, Suite 230
                  Irving, Texas  75063
                  Telephone:  (972) 444-8280
                  Facsimile:  (972) 869-3843

         with a copy to:

                  David H. Oden, Esq.
                  Haynes and Boone, LLP
                  1600 N. Collins, Suite 2000
                  Richardson, TX 75080
                  Telephone:  (972) 680-7550
                  Facsimile:  (972) 680-7551

         If to Lender to:

         Renaissance US Growth & Income Trust PLC
         c/o Renaissance Capital Group, Inc.
         8080 North Central Expressway, Suite 210-LB59
         Dallas, Texas 75206
         Attn:    Russell Cleveland
                  President and Chief Executive Officer
         Telephone:  (214) 891-8294
         Facsimile:  (214) 891-8291


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         Renaissance Capital Growth & Income Fund III, Inc.
         c/o Renaissance Capital Group, Inc.
         8080 North Central Expressway, Suite 210-LB59
         Dallas, Texas 75206
         Attn:    Russell Cleveland
                  President and Chief Executive Officer
         Telephone:       (214) 891-8294
         Facsimile:       (214) 891-8291

         with a copy to:

         Norman R. Miller, Esq.
         Kirkpatrick & Lockhart LLP
         1717 Main Street, Suite 3100
         Dallas, Texas 75201
         Telephone:  (214) 939-4906
         Facsimile:  (214) 939-4949


         If to Agent to:

         Renaissance Capital Group, Inc.
         8080 North Central Expressway, Suite 210-LB59
         Dallas, Texas 75206
         Attn:    Russell Cleveland
                  President and Chief Executive Officer
         Telephone:  (214) 891-8294
         Facsimile:  (214) 891-8291

         with a copy to:

         Norman R. Miller, Esq.
         Kirkpatrick & Lockhart LLP
         1717 Main Street, Suite 3100
         Dallas, Texas 75201
         Telephone:  (214) 939-4906
         Facsimile:  (214) 939-4949

Any notice delivered personally in the manner provided herein will be deemed
given to the party to whom it is directed upon the party's (or its agent's)
actual receipt. Any notice addressed and mailed in the manner provided herein
will be deemed given to the party to whom it is addressed at the close of
business, local time of the recipient, on the fourth business day after the day
it is placed in the mail, or, if earlier, the time of actual receipt.

                  (g) Capitalized terms used herein, unless otherwise defined
herein, have the definitions given them in the Loan Agreement among Borrower,
Lender and Agent.


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IN WITNESS WHEREOF, this Agreement has been duly executed as of the date and
year written above.

                             BORROWER:

                             INTEGRATED SECURITY SYSTEMS, INC.




                             By:
                                      ------------------------------------------
                                      C. A. Rundell, Jr., Chairman and
                                      Chief Executive Officer


                             LENDER:

                             RENAISSANCE US GROWTH & INCOME TRUST PLC


                             By:
                                      ------------------------------------------
                                      Russell Cleveland, Director


                             RENAISSANCE CAPITAL GROWTH & INCOME FUND III, INC.

                             By:      Renaissance Capital Group, Inc.,
                                      Investment Adviser

                                 By:
                                          --------------------------------------
                                          Russell Cleveland, President and Chief
                                          Executive Officer


                             AGENT:

                             RENAISSANCE CAPITAL GROUP, INC.


                             By:
                                      ------------------------------------------


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