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                                                                   Exhibit 10.47

   ASSIGNMENT AND ASSUMPTION OF LEASE AND CONSENT TO ASSIGNMENT AND ASSUMPTION

         THIS ASSIGNMENT AND ASSUMPTION OF LEASE AND CONSENT TO ASSIGNMENT AND
ASSUMPTION, made as of the 15th day of November 2001, (as the same may
hereinafter be amended or modified, the "Agreement"), by and among Winfield
Allen, Inc., a Colorado corporation (hereinafter the "Assignor"), Integrated
Information Systems, Inc., a Delaware corporation ("Assignee") and A.H. Root,
Limited Liability Company (hereinafter "Landlord").

RECITALS

         A. Assignor is tenant under that certain Office Lease, dated as of
August 14, 1999 with A.H. Root, Limited Liability Company, as landlord (the
"Lease"), for certain premises in the building located at 2401 15th Street,
Suite 350, Denver, Colorado 80202 (the "Premises"), as more particularly
described in the Lease.

         B. Assignor desires to assign certain of its interests under the Lease
to Assignee, and Assignee desires to assume certain of the obligations of
Assignor thereunder, in accordance with the terms and conditions of this
Agreement.

         C. Landlord desires to consent to the assignment and assumption
contained in this Agreement and to release Assignor from certain of its
obligations under the Lease, in accordance with the terms and conditions of this
Agreement.

         NOW THEREFORE, in consideration of the premises and mutual covenants
herein set forth, and for $10.00 and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agrees as follows:

         1. Assignment. Assignor hereby assigns, transfers and conveys unto
Assignee, effective as of the date hereof, all of Assignor's right, title and
interest in, to and under the Lease. From and after the date hereof, Assignor
and Landlord shall be responsible for, and hereby agree to indemnify and save
Assignee harmless from, any and all rent, claims, demands, actions, causes of
action, suits, proceedings, damages, liabilities, losses and costs and expenses,
including reasonable attorneys' fees, of every nature whatsoever, arising out of
Assignor's obligations under the Lease prior to the date of this Agreement.

         2. Assumption. Assignee hereby accepts the foregoing assignment,
transfer and conveyance and assumes the performance of all of the terms,
covenants, conditions and obligations of the Lease hereby assigned by Assignor
to Assignee from and after the date hereof. From and after the date hereof,
Assignee shall be responsible for, and hereby

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agrees to indemnify and save Assignor harmless from, any and all rent, claims,
demands, actions, causes of action, suits, proceedings, damages, liabilities,
losses and costs and expenses, including reasonable attorneys' fees, of every
nature whatsoever, arising out of Assignee's obligations under the Lease after
the date of this Agreement.

         3. Consent and Lease. Landlord hereby consents to the foregoing
Assignment and assumption and releases Assignor of and from any and all
liability to Landlord and the performance of any and all obligations on the part
of Assignor to be performed under the Lease arising out of Assignor's
obligations under the Lease prior to the date of this Agreement.

         4. Estoppel. Landlord represents, warrants, and covenants that (i) the
Lease is in full force and effect as of the date hereof and a true and correct
copy of the Lease is attached as Exhibit A; (ii) there have been no oral or
written modifications to the Lease except as shown on Exhibit A; (iii) there are
no actions, suits, proceedings or claims pending or threatened with respect to
or in any manner affecting the Lease or the Premises, nor does Landlord know of
any facts or circumstances which could reasonably form the basis for any such
actions, suits, claims or proceedings; (iv) all rent payments due under the
Lease have been paid in full as of the date hereof, and Assignor has fulfilled
all other obligations and made all other payments due thereunder; (v) Assignor
is not in default under any provision of the Lease; (vi) no other default
presently exists under the terms of the Lease; and (vii) no event has occurred
which, with the passage of time or action, would result in a default under the
Lease.

         5. Security Agreement. Landlord acknowledges that upon execution of
this Agreement, it will return to Assignor its security deposit of $25,466.22.
Concurrently therewith, Assignee will remit to Landlord a security deposit in
the same amount.

         6. Agreement Binding. This Agreement shall be binding upon and inure to
the benefit of the parties hereto and their heirs, executors, administrators,
successors in interest and assigns.

         7. Governing Law. The validity of this Agreement and of any of its
terms of provisions, as well as the rights and duties of the parties under this
Agreement shall be governed by and interpreted in accordance with the laws of
the State of Colorado.

         8. Enforcement. Any provision of this Agreement which is finally
determined by competent authority to be prohibited or unenforceable in any
jurisdiction shall, as to such provision and jurisdiction only, be deemed
severed to the extent of such prohibition or unenforceability, and, subject to
such severance, this Agreement shall continue in force and effect in accordance
with its other terms and conditions.

         9. Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, and all such
counterparts when taken together shall for all purposes constitute a single
instrument, binding on all parties hereto, notwithstanding that all parties
shall not have executed the same counterpart.

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This Agreement may be executed via facsimile, and such Agreement executed via
facsimile shall have the same force and effect as an original document and shall
be legally binding upon the parties.

         IN WITNESS WHEREOF, the parties hereto have executed this Assignment
and Assumption of Lease and Consent to Assignment and Assumption as of the date
first above written.

                                       ASSIGNOR:

                                       WINFIELD ALLEN, INC.

                                       By: /s/ Mark Day    11/15/01
                                           ----------------------------------
                                       Title: President


                                       ASSIGNEE:

                                       Integrated Information Systems, Inc.

                                       By: /s/ William Mahan
                                           ----------------------------------
                                       Name:  William Mahan
                                       Title: EVP/CFO


                                       LANDLORD:

                                       A.H. Root, Limited Liability Company

                                       By:/s/ Michael D. Plante   11/15/01
                                           ----------------------------------
                                       Name:  Michael D. Plante
                                       Title: Managing Member