EXHIBIT 5.1



December 5, 2001



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

Re:  Registration Statement on Form S-8 of 1,500,000 Shares of Common Stock of
     Integrated Security Systems, Inc.

Gentlemen:

We have acted as special counsel to Integrated Security Systems, Inc., a
Delaware corporation (the "Company"), in connection with the preparation of the
Registration Statement on Form S-8 (the "Registration Statement"), filed with
the Securities and Exchange Commission under the Securities Act of 1933, as
amended, relating to the registration of 1,500,000 shares (the "Shares") of
Common Stock, par value $.01 per share (the "Common Stock"), of the Company
which may be issued from time to time upon the exercise of options granted or
which may be granted by the Company pursuant to the Integrated Security Systems,
Inc. 1997 Long-Term Incentive Plan (the "Plan").

In connection therewith, we have examined (i) the Certificate of Incorporation
and the Bylaws of the Company, as amended; (ii) minutes and records of the
corporate proceedings of the Company with respect to the adoption of the Plan
and the issuance of the Shares or options pursuant to the Plan; (iii)
certificates of certain officers and directors of the Company; (iv) the Plan and
the forms of agreements pertaining thereto; and (v) such other documents as we
have deemed necessary for the expression of the opinions contained herein.

As to various questions of fact material to the opinions expressed below, we
have also relied in part and to the extent we deem reasonably appropriate upon
representations made to us by officers and directors of the Company or its
agents, without independent check or verification of their accuracy. The law
covered by the opinions expressed herein is limited to the federal laws of the
United States and the General Corporation Law of the State of Delaware.

In making the foregoing examination, we have assumed the genuineness of all
signatures and the authenticity of all documents submitted to us as originals,
and the conformity to original documents of all documents submitted to us as
certified or photostatic copies. Furthermore, we have assumed that all stock
option exercise prices will exceed $.01 per share (the par value of the Common
Stock).

Based upon the foregoing, and having due regard for such legal considerations as
we deem relevant, we are of the opinion that the 1,500,000 shares of Common
Stock covered by the Registration Statement which may be issued from time to
time in accordance with the terms of the Plan have been duly authorized for
issuance by the Company, and, when so issued in accordance with the






terms and conditions of the Plan and any related option agreements, will be
validly issued, fully paid and non-assessable.

We hereby consent to the filing of this opinion with the Securities and Exchange
Commission as an exhibit to the Registration Statement.

                                      Very truly yours,



                                      /s/ HAYNES AND BOONE, LLP
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