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                                                                   Exhibit 10.51



                              SETTLEMENT AGREEMENT

         THIS AGREEMENT (the "Agreement") is made and entered into as of October
14, 2002 by and between INTEGRATED INFORMATION SYSTEMS, INC., a Delaware
corporation (and successor by merger to Integrated Information Systems, Inc., an
Arizona corporation) ("IIS"), and COMERICA BANK - CALIFORNIA, a California
corporation, on behalf of itself and all of its divisions (collectively,
"Comerica"). (IIS, on the one hand, and Comerica on the other hand, shall be
referred to herein collectively as the "Parties" and each, as a "Party").


                                    RECITALS

         A. IIS and Comerica are parties to those certain agreements more
particularly described on Exhibit A attached hereto (collectively, the
"Agreements").

         B. Certain disputes have arisen between IIS and Comerica with respect
to the rights and obligations of the Parties under the Agreements and otherwise.
On or about August 13, 2002, IIS filed suit against Comerica in the Maricopa
County Superior Court, Phoenix, Civil Action No. CV2002-015787 (the
"Litigation").

         C. To settle their dispute and avoid the cost, distraction and
uncertainty of further litigation, the Parties have decided to settle the claims
asserted by IIS against Comerica in the Litigation ("Claims"), as well as any
other obligations or potential claims either party may have against the other
under the Agreements or otherwise, except for the obligations expressly set
forth in this Agreement. By agreeing to this settlement, neither Party admits
the validity of the other Party's claims or defenses or threatened claims or
defenses.


                                    AGREEMENT

         NOW, THEREFORE, in consideration of the acts, payments, covenants and
mutual agreements herein described and agreed to be performed, and for other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, IIS and Comerica do hereby mutually agree as follows:

         1. Definitions.

            1.1 "Approval Contingency" is defined in Section 2.3 of this
Agreement.

            1.2 "Liability" means, to the extent based in any way upon or
relating in any way to acts, omissions or circumstances occurring or existing
(whether known or unknown) before or after the date of this Agreement, any
liability, obligation or responsibility of any kind, character or description,
regardless of the legal principle or theory upon which the same may be based,
whether known or unknown, liquidated or unliquidated, contingent or absolute,
accrued or unaccrued, matured or unmatured, insured or uninsured, joint or
several, determined or undetermined, determinable or otherwise, and shall
include, without limitation, any claim, judgment, litigation, proceeding, damage
(including, without limitation, actual, punitive and consequential damages),
loss, penalty, strict or other liability in tort, liability for any breach of
contract or agreement, civil or criminal violation of law, cost, expense
(including, without



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limitation, attorneys' fees and costs), cost of defending any claim, amount or
cost of any judgment or settlement.

            1.3 "Person" means any natural person, corporation, company,
partnership, association, trust, estate, or other entity or organization, the
media, and any governmental representative, agency or authority.

            1.4 "Warrant" means that certain Warrant, issued as of December 18,
1997, by IIS to Imperial Bank, a California banking corporation, predecessor in
interest to Comerica, a copy of which is attached hereto as Exhibit B.

         2. Settlement Payment and Termination of Agreements.

            2.1 Payment. Upon execution and delivery of this Agreement and
satisfaction of the Approval Contingency, IIS shall pay to Comerica an amount
equal to $400,000.00 (the "Settlement Amount") by wire transfer or in other
immediately available funds, within three (3) business days after satisfaction
of the Approval Contingency. In the event that the Settlement Amount is not paid
by the close of business on November 5, 2002, this Agreement shall be terminated
automatically.

            2.2 Termination of Agreements.

                2.2.1 Upon execution and delivery of this Agreement,
satisfaction of the Approval Contingency and payment of the Settlement Amount,
all obligations and liens under the Agreements shall be deemed fully satisfied,
discharged and released and the Agreements shall automatically terminate and be
of no further force and effect; provided, that notwithstanding any provision of
this Agreement to the contrary, the Warrant shall remain in full force and
effect according to its terms.

                2.2.2 Upon execution and delivery of this Agreement,
satisfaction of the Approval Contingency and payment of the Settlement Amount,
Comerica authorizes IIS to complete and file one or more UCC financing statement
amendments as may be necessary to terminate any financing statement(s)
previously filed which name IIS as the debtor and constitutes IIS its
attorney-in-fact and agent to sign the names of Comerica and its predecessors
and affiliates to any such financing statements.

            2.3 Approval Contingency. The obligations of IIS under this
Agreement are subject to the condition that IIS shall have obtained on or before
October 31, 2002 (i) the approval of the IIS Board of Directors of this
Agreement; (ii) accounts receivable backed financing or terms and conditions
satisfactory to IIS and its lender (the "New Lender") and (iii) acceptance of
settlement offers by the major creditors of IIS designated by IIS and the New
Lender (the "Approvals and Financing") and shall have notified Comerica in
writing that the Approvals and Financing have been obtained (the "Approvals
Contingency").

         3. Mutual Release, Indemnity and Covenant Not to Sue. For good and
valuable consideration, upon execution and delivery of this Agreement and
satisfaction of the Approval Contingency and payment of the Settlement Amount:


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            3.1 Each Party hereby releases, exonerates and forever and
unconditionally discharges the other Party and its respective officers,
directors, predecessors, successors, employees, representatives, shareholders,
attorneys, and assigns from any and all Liability now or hereafter relating to,
or arising directly or indirectly out of, the Claims, the Litigation, the
Agreements, the relationship between the parties or otherwise, except: (i) for
the obligations expressly set forth in this Agreement; and (ii) that Comerica
will retain the Warrant.

            3.2 Each of the Parties expressly waives any benefits it may have
under Section 1542 of the Civil Code of the State of California which provides
as follows:

            "A general release does not extend to claims which the creditor does
            not know or suspect to exist in his favor at the time of executing
            the release, which if known by him must have materially affected his
            settlement with the debtor,"

and any and all provisions, rights, and benefits of any similar statute or law
of Arizona or of any other jurisdiction, to the fullest extent it may lawfully
waive such provisions, rights or benefits. The Parties acknowledge that they are
aware that they may hereafter discover facts in addition to or different from
those which they now know or believe to be true with respect to the subject
matter of this Agreement, but it is their intention to and they do hereby fully,
finally, and forever settle and release any and all claims encompassed by this
Agreement, known or unknown, suspected or unsuspected, claimed or concealed,
asserted or unasserted, contingent or noncontingent, which now exist, may
hereafter exist, or may heretofore have existed, and without regard to the
subsequent discovery or existence of such different or additional facts.

            3.3 No Party will seek recovery of fees, costs or expenses,
including without limitation attorneys' fees or costs, against any other Party
with respect to this Agreement or the matters that are the subject of this
Agreement, each Party to bear its own such fees, costs and expenses. Within five
(5) business days after the execution and delivery of this Agreement by both
parties, IIS and Comerica will cause their attorneys to file in the Litigation a
stipulation for dismissal with prejudice.

            3.4 Each Party agrees and covenants (i) to indemnify, defend and
hold the other Party harmless from any action, proceeding or claim of any kind
by any person in any court or agency or before any arbitral or other tribunal in
respect of any matter released by such indemnifying Party in this Agreement or
any Liability associated therewith, and (ii) to take all necessary actions to
ensure that no other person within its direct or indirect control shall assert
or commence any action, proceeding or claim of any kind in any court or agency
or before any arbitral or other tribunal in respect of any such matter or any
Liability associated therewith or to encourage, assist or cooperate with any
person pursuing or asserting any such matter.

            3.5 The Parties agree that in entering this Agreement, it is
understood and agreed that each Party relies wholly upon its own judgment,
belief and knowledge and that no representations or statements regarding the
above-mentioned matters or regarding any other matters made by the other Party
or the others who are hereby released or by any other person or persons
representing them has influenced either Party to any extent whatsoever in
entering this Agreement.


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            3.6 Comerica represents and warrants that it has not assigned or
subrogated any of the Claims or Agreements or authorized any other person or
entity to assert any Claim in its stead or on its behalf.

         4. Confidentiality. The Parties shall maintain in confidence and shall
not disclose the existence or terms of this Agreement or any of the facts and
circumstances surrounding this Agreement, including without limitation those
concerning or related to the Claims and the Litigation, to any person other than
as required by applicable law or with the prior written consent of the other
Party; provided, that IIS may disclose this Agreement to its lenders and
auditors. However, this Confidentiality clause shall not prohibit the parties
from abiding by subpoenas or other forms of legal process, including regulatory
inquiries from governmental bodies.

         5. No Admission. The Parties agree that this Agreement and the terms
and conditions hereof, may never be construed as a confession or admission of
liability by either Party in any suit or proceeding or admitted into evidence
against either Party, except in any litigation arising out of this Agreement.

         6. Remedies. Except as expressly stated herein, this Agreement is fully
effective upon execution and delivery by the parties. Except as expressly stated
herein, this Agreement is not dependent upon and may not be defeated by any
further performance or non-performance of any obligations, conditions,
covenants, promises, warranties or similar undertakings to be performed or not
to be performed in the future by the parties. Except as expressly stated herein,
the breach of any such duties or this Agreement (other than payment of the
Settlement Amount) shall give rise only to a cause of action for that breach and
shall not reinstate the Claims released, or the Agreements terminated, under
this Agreement.

         7. Successors and Assigns. This Agreement is and shall be binding upon
(i) the officers, directors, successors and assigns of each Party, (ii) each
past, present, direct or indirect parent, subsidiary, division or affiliated
entity of each Party, and (iii) each past or present agent, representative or
shareholder of the respective Parties.

         8. Governing Law. This Agreement shall in all respects be interpreted,
construed and governed by and in accordance with the laws of the State of
Arizona, disregarding any conflicts of law provision which may otherwise require
the application of the law of another jurisdiction.

         9. Counterparts. This Agreement may be executed in counterparts,
including by telecopy signatures, each of which shall be deemed an original, but
all of which together shall constitute one and the same agreement.

         10. Entire Agreement. This Agreement constitutes the entire agreement
among the Parties with respect to the subject matter hereof. This Agreement
shall not be terminated, altered, amended, modified or otherwise changed by any
oral communications of any kind or character, or by any written communication,
unless signed by a duly authorized representative of each of the Parties.


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         11. Notices. Any notices that may be required under this Agreement
shall be in writing, shall be effective on the earlier of the date when
received, the date of telecopy machine confirmation, or the third day following
mailing, and shall be given by personal service, by certified or registered mail
return receipt request, or by telecopy, with machine confirmation of receipt, to
the addresses set forth below, or to such other addresses as may be specified in
writing to all parties hereto.

                  If to IIS:


                           1480 South Hohokam Drive
                           Tempe, Arizona 85281
                           Attn: Mark Rogers
                           Facsimile (480) 317-8010

                  With a copy to:

                           Osborn Maledon, P.A.
                           2929 N. Central Ave., Suite 2100
                           Phoenix, Arizona 85012-2794
                           Attn: William M. Hardin, Esq.
                           Facsimile: (602) 640-9050

                  If to Comerica:

                           Comerica Bank - California
                           9220 South La Cienega Blvd., Suite 623
                           Inglewood, California 90301
                           Attn: Gary Irick
                           Facsimile: (310) 338-6160

                  With a copy to:

                           Quarles & Brady Streich Lang, LLP
                           Two North Central
                           Phoenix, Arizona 85004
                           Attn: John R. Clemency
                           Facsimile: (602) 229-5412

         12. Additional Acts and Documents. Each Party hereto agrees promptly to
do all such things and take all such actions, and to make, execute and deliver
such other documents and instruments (including, but not limited to UCC
termination statements), as shall be reasonably requested to carry out the
provisions, intent and purpose of this Agreement.

         13. Authority. Each party warrants that any person executing this
Agreement on its behalf has the full authority to do so.


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         IN WITNESS WHEREOF, the Parties have caused this Agreement to be duly
executed by their duly authorized representatives with effect from the date
first set forth above.

                                            INTEGRATED INFORMATION SYSTEMS, INC.


                                            By:  /s/ Mark N. Rogers
                                            Name:  Mark N. Rogers
                                            Title:  SVP, General Counsel


                                            COMERICA BANK - CALIFORNIA


                                            By:  /s/ Gary Irick
                                            Name:  Gary Irick
                                            Title:  Vice President











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