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                                                                   Exhibit 10.22

                          MASTER TRANSACTION AGREEMENT

      THIS MASTER TRANSACTION AGREEMENT (this "Agreement") is executed to be
effective as of 15 May 1996 (the "Effective Date") by and between:

      THE FIRST INVESTMENT VOUCHER FUND, an open joint stock company established
      and existing under the laws of the Russian Federation, having its
      principal place of business at Trubnikovsky 21/2, Moscow, Russian
      Federation, and represented by the Chairman of its Board of Directors, Mr.
      Michael Yu. Chebotarev, who is acting on the basis of the Fund's charter
      ("Fund"); and

      PIONEER REAL ESTATE ADVISORS INC., a company organized and existing under
      the laws of the State of Delaware, U.S.A., having its principal place of
      business at 60 State Street, Boston, Massachusetts, U.S.A., and
      represented by its President, Stephen G. Kasnet, who is acting on the
      basis of a resolution of the Board of Directors ("PREA").

                                    RECITALS:

A. The Fund is the owner of an office building known as the Meridian Commercial
Tower, located at Ulitsa Smolnaya 24/D, 125445 Moscow, Russia according to the
system of street names and numbering now in official use in the City of Moscow,
Russia ("Building"). The construction and fit out of the Building is unfinished,
and the Building is not yet fully let.

B. PREA is a real estate development and management company with the experience
and resources necessary to: (1) complete construction of the Building, (2) lease
the office space therein to reputable Tenants, and (3) manage the Property
(collectively the "Transaction").

C. Simultaneously with this Agreement, the parties shall execute the Master
Lease Agreement attached hereto as Appendix A, the Construction Completion
Agreement attached hereto as Appendix B and the Property Management Agreement
attached hereto as Appendix C (collectively hereinafter the "Underlying
Agreements"), the parties desire to set forth their understanding and mutual
responsibilities with regard to the Transaction. This Master Transaction
Agreement is designed to amend and supplement the Underlying Agreements and to
further define the parties' obligations with respect to the Transaction.

NOW THEREFORE, in consideration of the mutual promises and covenants exchanged
herein, the parties hereby agree as follows:

                                    AGREEMENT

                           ARTICLE 1. THE TRANSACTION

1.1 Purpose. The parties hereby affirm and agree that this Agreement amends and
supplements the Underlying Agreements and further defines the obligations of the
parties with respect to the Transaction. This Agreement defines the structure,
basic terms and conditions governing the Transaction and the respective
obligations of the parties. Among other terms

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and conditions described herein, this Agreement supplies the formula by which
the parties shall determine the quarterly Rent payable to the Fund under the
Master Lease Agreement, and provides the mechanism whereby PREA shall offset its
Unrecoverable Expenses and Construction Costs incurred under the Construction
Completion Agreement against its Rent obligation.

1.2 Transaction Description. The Fund shall, through the Underlying Agreements,
engage PREA to (1) complete construction of the Building; (2) sublease the
office space therein to good and reputable Tenants; and (3) manage the Building.

1.3 Term. This Agreement shall be effective as of the Effective Date, and shall
expire upon the expiration or earlier termination of the last of the Underlying
Agreements to remain in effect.

1.4 Agreement Controls. If any of the provisions of this Agreement conflict in
whole or in part with the provisions of the Underlying Agreements, the
provisions of this Agreement shall control. Notwithstanding the forgoing, the
Master Lease shall be governed and interpreted according to the choice of law
and dispute resolution provisions contained in Article 11 therein, and not by
the choice of law and dispute resolution provisions of this Agreement.

                    ARTICLE 2. DEFINITIONS AND INTERPRETATION

      The following terms shall have the meanings given for this and the
Underlying Agreements:

2.1 Business Day. "Business Day" means any day, other than Saturday, Sunday or
any public holiday in the United States of America or in the Russian Federation.

2.2 Construction Costs. "Construction Costs" means any costs for materials,
labor and services identified in the Construction Budget, or otherwise approved
as provided in this Agreement or the appropriate Underlying Agreements, and
incurred by PREA to complete construction of the Building. "Construction Costs"
shall not include the cost of any financing obtained by PREA to complete
construction.

2.3 Construction Budget. The "Construction Budget" is the budget prepared by
PREA and approved by the Fund in writing containing all costs for materials,
labor and services necessary to complete construction of the Building, including
all historic costs which have been paid or agreed as being due under any of the
underlying Agreements and all future costs and expenditures to be made. The
Construction Budget is attached as Appendix A to the Construction Completion
Agreement.

2.4 Construction Fee. The "Construction Fee" means PREA's once-quarterly fee for
completing construction of the Building pursuant to the Construction Completion
Agreement, which shall be one percent of the Construction Costs incurred by PREA
during each calendar quarter.

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2.5 Expenses. "Expenses" means the quarterly total of (a) Operating Expenses
(except amounts collected from Tenants towards Land rent and property taxes),
plus (b) Leasing Costs, plus (c) any amount of Shortfall from previous quarters
and interest on such amount at the rate of two percent per quarter (to the
extent PREA holds any advance rent payments collected from Tenants and not yet
attributable to Gross Collections, the Shortfall shall be reduced by the
advances so held for purposes of calculation of interest due with respect to the
Shortfall); plus (d) interest, costs and fees, if any, due or incurred with
respect to financing PREA obtained pursuant to the Construction Completion
Agreement, plus (e) quarterly payment of the Construction Fee.

2.6 Gross Collections. "Gross Collections" means the total amounts of: (a)
Tenant rent payments, (b) Tenant contributions toward Operating Expenses (except
contributions for the Property Management Fee), (c) interest earned on amounts
of advanced rents and security deposits paid by Tenants and held by PREA (except
amounts of such interest that are payable to Tenants pursuant to their lease
agreements), (d) parking fees, and (e) telecommunications commissions from
Tenant use of telecommunications facilities in the Building, all of which shall
be exclusive of value added or other taxes that are due with respect to the
Gross Collections, that are collected with respect to the Building, during the
quarter in which PREA is paying Rent, or prior quarters, and attributable to
that or prior quarters as PREA may reasonably determine.

2.7 Land. The "Land" means the 13,035 square meters of land located at Ulitsa
Smolnaya 24/D that was leased to the Fund by the Moscow Government according to
a 49 year lease agreement No. M-09-000979, dated 6 September 1994.

2.8 Leasing Costs. "Leasing Costs" means the costs incurred by PREA in
connection with leasing the office space in the Building, including fees and
commissions payable to real estate brokers, associated legal fees, and the
amounts of any rent discounts or other leasing incentives offered to Tenants.

2.9 Operating Budget. "Operating Budget" means PREA's annual budget for
operating the Building, including PREA's estimate of annual Gross Collections
and Operating Expenses and indicating, to the extent possible, which if any
expenses will not be recovered through Tenant contributions to Operating
Expenses.

2.10 Operating Expenses. "Operating Expenses" means the total costs, charges,
expenses and disbursements of every kind and nature that must be paid in
connection with the management, operation, maintenance, improvement and repair
of the Property, including the following:

      (a) Utilities. The cost of utilities, including heat, air conditioning,
      water, steam, fuel and electricity other than that which is supplied to
      individual Tenants and paid for by them separately.

      (b) Maintenance Fees. The cost of Building maintenance including fees for
      interior and exterior maintenance, upkeep and repair of the Property as
      well as the Building heat, air conditioning, plumbing, mechanical,
      electrical and other systems;

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       landscaping, ground maintenance and snow removal, including the cost of
       equipment and tools, the cost of servicing such equipment and
       contributions to any sinking funds that PREA may create from time to time
       in order to spread the cost of such maintenance, upkeep and repair more
       equitably among Tenants over the terms of their lease agreements.

       (c) Management Expenses. The portion of the Property Management Fee, if
       any, not recovered from Tenants, and other fees, costs and expenses
       related to property management including accounting, catering,
       electrical, extermination, financial, janitorial, legal, plumbing,
       security and window cleaning services, as well as the total amount of
       salaries and benefits payable to Building staff, and the cost of
       providing a "drivers' room" in the Building.

       (d) License Fees. The cost of licenses, permits, inspections and
       compliance with any health and fire safety or other governmental rule or
       regulation imposed upon either of the parties with respect to the
       Property including the cost of fire protection.

       (e) Insurance Premiums. The cost of premiums for property and other
       insurance, including rental value and liability insurance, and any costs
       incurred in obtaining a valuation of the reinstatement costs for the
       purposes of arranging such insurance.

       (f) Taxes. The cost of all general and special land and property taxes,
       value added taxes and all other taxes, charges, rates, levies and
       assessments of whatever nature levied, assessed or collected by any
       governmental or quasi-governmental authority upon or with respect to
       ownership or operation of the Building and the Land, other than the
       Fund's profits taxes.

2.11 Parking Lot. The "Parking Lot" means the paved parking area on the Land and
adjacent to the Building that has been prepared by the Fund for use by Tenants,
their employees and visitors.

2.12 Property. "Property" means the Building, Parking Lot and Land.

2.13 Property Management Fee. The "Property Management Fee" means the fee
payable to PREA in consideration for PREA managing the Property pursuant to the
Property Management Agreement.

2.14 Rent. "Rent" means the quarterly amount PREA shall pay the Fund in exchange
for use of the Property.

2.15 Shortfall. "Shortfall" shall be as defined in section 3.1.1.

2.16 Tenant. "Tenant" means any individual, legal entity or representative of a
legal entity that has executed a lease for office space in the Building with
PREA.

2.17 Carryover. "Carryover" shall be as defined in section 3.1.3.

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2.18 Unrecoverable Expenses. "Unrecoverable Expenses" means all expenses
incurred by PREA pursuant to the Property Management Agreement that it cannot
recover from Tenants as part or their contributions toward Operating Expenses.

2.19 Unrecoverable Expenses Budget. "Unrecoverable Expenses Budget" is the
quarterly budget of Unrecoverable Expenses prepared by PREA.

                ARTICLE 3. RIGHTS AND OBLIGATIONS OF THE PARTIES

3.1  Rent and Construction Costs.

      3.1.1 Determine Rent Under the Master Lease. Not later than the 15th day
      of the first month of each calendar quarter, PREA shall determine the
      quarterly Rent payable to the Fund under the Master Lease. The Rent shall
      be an amount equivalent to the larger of: (1) U.S. $250,000.00 per
      quarter; or (2) Gross Collections for the previous quarter minus Expenses
      for the previous quarter, which shall be exclusive of any value added or
      similar taxes thereon. Upon determination of the Rent as provided herein,
      PREA and the Fund shall amend the Master Lease to reflect the new Rent due
      thereunder as provided in section 3.1.4 hereunder and section 3.2 of the
      Master Lease. Notwithstanding the foregoing, if the parties fail to amend
      the Master Lease as provided herein, then the Rent for the quarter shall
      be an amount equivalent to U.S. $250,000.00. Determination of the Rent due
      to the Fund hereunder may result in a shortfall to PREA which shall be
      recovered over time as provided in section 3.1.3 below. For the purposes
      of this Agreement and the Underlying Agreements, "Shortfall" shall be the
      difference between U.S. $250,000.00 and the result obtained by subtracting
      Expenses from Gross Collections when that result is less than U.S.
      $250,000.00.

      3.1.2 Determine Quarterly Construction Costs and Unrecoverable Expenses.
      PREA shall determine the amount of Construction Costs and Unrecoverable
      Expenses incurred since the 25th day of the last month of the previous
      quarter, for the purpose of determining what amounts, if any, should be
      remitted to the Fund.

      3.1.3 Reconcile Rent, Construction Costs and Unrecoverable Expenses. PREA
      shall offset the Rent determined in accordance with section 3.1.1, with
      the Construction Costs, Unrecoverable Expenses, Shortfall resulting from
      calculations under section 3.1.1 and Carryover from previous quarters to
      establish the amount PREA shall transfer to the Fund, if any. If the
      Construction Costs, Unrecoverable Expenses, Shortfall and Carryover are
      greater than the Rent obligation for any given quarter, then PREA shall be
      entitled to carry over and deduct the amount in excess of the Rent
      obligation from its Rent obligation in subsequent quarters ("Carryover").

      3.1.4 Amend Master Lease, Execute Act. The parties shall execute quarterly
      amendments to the Master Lease in accordance with section 3.2 thereof,
      restating the amount of Rent due thereunder, as well as a separate
      quarterly acts evidencing the

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      reconciliation of the Rent with the Construction Costs, Unrecoverable
      Expenses, Shortfall and Carryover.

      3.1.5 Special Adjustment due to VAT Exemption. Because of the delays in
      value added tax ("VAT") refunds from the Russian tax authorities and
      because such delays would make it undesirable for PREA to undertake its
      obligations under this Agreement and the Master Lease, the parties have
      reached the following agreement: Notwithstanding the amounts due to Fund
      in accordance with the provisions of section 3.1.3 herein, to the extent
      PREA shall accept, as part of Gross Collections, any Tenant rent payments
      that are not subject to VAT ("VAT Exempt Payments") and with respect to
      which VAT has not been collected by PREA as provided in applicable
      legislation, PREA shall satisfy its obligation to the Fund in the amount
      equal to Rent due, as provided in section 3.1.1, minus the amount of VAT
      not collected from Tenants who qualify for the VAT exemption outlined
      above ("Temporary Debt"). The Temporary Debt shall be duly documented by
      the parties and shall be reflected appropriately on in the parties'
      accounting books. The Temporary Debt shall remain as the obligation of
      PREA to the Fund and shall be repaid to the Fund over time as the VAT
      related to the VAT Exempt Payments is recovered by PREA from the Russian
      tax authorities. To the extent PREA fails to recover VAT related to VAT
      Exempt Payments from the Russian tax authorities, after good faith efforts
      to do so, the Temporary Debt shall be settled between PREA and the Fund in
      a manner mutually agreed by the parties, provided that such settlement may
      not result in losses to PREA or the Fund. Should there be a threat of loss
      to either party, the parties shall, within 15 Business Days, agree on a
      method of avoiding such losses (including any required VAT payments) and
      such agreement may, subject to satisfaction of financing obligations,
      envision direct lease agreements between the Fund and Tenants.

3.2 Mutual Settlement of Accounts. All payments due in accordance with the
Underlying Agreements shall be made not later than the 25th day of the last
month of each calendar quarter unless otherwise specified. If any payment is not
made within 15 Business Days after it is due, the party expecting payment shall
demand payment from the other party in writing, and the other party shall have
five Business Days to make the payment. If payment is not made within five
Business Days after receipt of such notice, the party owing the payment shall
owe interest at the rate of 1% per month of the amount due, compounded monthly
and calculated on a pro rata basis with effect from the date due ("Penalty").
Notwithstanding the foregoing, the Penalty shall not apply to the Temporary
Debt. Upon the expiration or earlier termination of this Agreement or any of the
Underlying Agreements, PREA at its discretion, may terminate any of the
Underlying Agreements with reasonable notice not inconsistent with the
provisions of the relevant Underlying Agreement and without any further
obligations to the Fund. The parties shall settle their accounts under such
agreement and any of the other Underlying Agreements at PREA's discretion, and
pay over any amounts remaining due and outstanding within 20 Business Days. The
settlement obligations in this and the Underlying Agreements shall survive the
expiration or earlier termination of this Agreement.

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3.3 Mutual Assistance. The parties shall cooperate and shall reasonably assist
each other to facilitate relationships with representatives and officials of the
Russian Federation federal, local, and municipal governments, including tax
authorities.

3.4 Termination of Underlying Agreements. In addition to possible termination of
each of the Underlying Agreements in accordance with each document's termination
provisions, the Master Lease shall terminate upon any sale of the Building, and
the Property Management Agreement shall, if in effect at the time of any such
sale of the Building, continue in effect for one year from the closing date of
such sale, unless extended according to written terms then agreed between the
parties.

                          ARTICLE 4. DISPUTE RESOLUTION

4.1 Choice of Law. This Agreement and the Underlying Agreements shall be
governed and construed in accordance with the laws of the Commonwealth of
Massachusetts, U.S.A.

4.2 Dispute Resolution. The parties shall attempt to resolve any dispute arising
from or in connection with this Agreement or any of the Underlying Agreements,
including any question of its existence, validity or termination, by amicable
negotiation. If the parties are unable to resolve the dispute within 20 Business
Days, then either party may refer the dispute to, and the parties hereby agree
to the jurisdiction of, arbitration by the American Arbitration Association, in
accordance with its International Arbitration Rules. The arbitration tribunal
shall consist of one arbitrator appointed by the administrator thereunder, and
shall take place in the City of Boston, Massachusetts, U.S.A. The arbitration
shall proceed and all documents shall be presented in the English language. Any
award of the arbitrator shall be final and binding on the parties.

                        ARTICLE 5. ADDITIONAL PROVISIONS

5.1 No Assignment. Neither party shall assign, delegate and/or transfer to third
parties its rights and obligations under this Agreement without the other
party's prior written consent, except PREA may assign its rights and obligations
under this Agreement to any entity controlling, controlled by or under the
common control of PREA. This Agreement shall be binding upon and inure to the
benefit of the parties, their successors in interest, if any, and their
respective permitted assigns and transferees.

5.2 No Partnership. Neither this Agreement nor the Underlying Agreements are
intended nor shall be construed to create a partnership, joint venture or
similar relationship between the parties, nor shall it be construed to create
any rights in any third parties against the parties hereto.

5.3 Severability. If any provision of this Agreement or any of the Underlying
Agreements is or becomes invalid, ineffective, unenforceable or illegal for any
reason, the remaining provisions shall continue in full force and effect. The
parties shall amend any invalid provision so as to fulfil their original intent
to the maximum extent possible.

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5.4 Amendments. The parties may amend this Agreement or any of the Underlying
Agreements at any time, provided such amendments are made in writing, designated
as an amendment to the respective agreement, and duly signed by both parties.

5.5 Notices. Notices required or permitted under this Agreement or any of the
Underlying Agreements shall be in writing and shall be delivered by: (1) an
internationally accepted courier service, with signed receipt of delivery made;
(2) hand-delivery, with signed receipt of delivery made; or (3) by facsimile,
with a confirmation copy sent by internationally accepted courier service or
hand-delivery, addressed to the parties hereto as follows (unless changed by a
notice in accordance herewith from the party changing its address to the other
party):

       To PREA                 Robert Nault, Stephen G. Kasnet
                               Pioneer Real Estate Advisors, Inc
                               60 State Street
                               Boston, MA 02109-1820
                               FAX: 1-617-422-4293

       with a copy to          Grenville Carr-Jones
                               Management Office
                               Meridian Commercial Tower
                               Ulitsa Smolnaya 24/D
                               125445 Moscow, Russia
                               FAX: 7-095-960-2920

       To the Fund:            Michael Chebotarev, Timothy Frost
                               First Investment Voucher Fund
                               21/2 Trubnikovsky Pereulok
                               Moscow, Russia
                               FAX: 7-095-956-6181

Notices delivered pursuant to the terms of this section shall be deemed
effective within three calendar days from the date when the notice is sent to
the foregoing addresses.

5.6 Force Majeure. The parties shall be relieved of responsibility for any
nonfulfillment in whole or in part of their obligations under this Agreement or
any of the Underlying Agreements, if such nonfulfillment is caused by
force-majeure circumstance, including but not limited to such events as war,
civil uprising, rebellion, civil or military conflict, acts of sabotage, strike,
lockout, fire, floods, or other natural disasters. Notwithstanding the
foregoing, if as a result of such force majeure circumstances, one of the
parties is unable to fulfil its obligations, that party shall inform the other
party immediately and take all measures that it deems expedient in order to
protect the interests of the other party. The parties shall not have the right
to demand compensation for any losses arising as a consequence of such
unfulfilled obligations.

5.7 Liability of PREA. PREA shall not be liable directly or vicariously for the
acts or omissions of, nor any damages caused to the Fund by any other party
involved in the Transaction, including the acts or omissions of the construction
contractors. Except for PREA's own acts of wilful misconduct or gross
negligence, PREA shall not be liable for any

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damages caused to the Fund for actions taken in good faith in connection with
performing its obligations under this Agreement and the Underlying Agreements.

5.8 Limitation on Damages. Subject to section 5.7, if either party breaches any
of its obligations under this Agreement of any of the Underlying Agreements,
such party shall compensate the other party for any actual damages, but shall
not be liable for any subsequent or consequential damages suffered as a result
of the breach.

5.9 Indemnification. Except when caused by the wilful misconduct or gross
negligence of PREA, the Fund shall indemnify and hold PREA harmless from and
against all claims, costs, damages, judgments, attorneys' fees, expenses,
obligations and liabilities of any kind or nature that PREA may incur or sustain
in good faith in connection with or arising out of its obligations under this
Agreement or any of the Underlying Agreements. Notwithstanding the foregoing,
the Fund shall not be liable and shall not indemnify PREA for any claims,
damages or judgements related to any labor disputes arising from employment
relationships established by PREA.

5.10 Cost and Expenses. Wherever in this Agreement or any of the Underlying
Agreements, a provision is made for the doing of any act by any person it is
understood and agreed that such act shall be done by such person at its own cost
and expense unless otherwise stated.

5.11 Interpretation. Whenever the context may require, any pronoun shall include
the corresponding masculine, feminine and neuter forms, and with respect to the
parties shall include where the context does not prohibit, their respective
permitted successors and assigns. The words "include," "includes" and
"including" shall be deemed to be followed by the phrase "without limitation."
All references to articles, sections, appendices and parties shall mean
articles, sections, appendices of and parties to this Agreement, unless
otherwise stated. All headings are inserted for convenience only and shall not
affect construction of this Agreement

5.12 Entire Agreement. This Agreement and the Underlying Agreements contain the
entire agreement between the parties with respect to the subject matter herein,
and no representations or agreements, oral or otherwise, between the parties not
embodied within the documents identified in this section 5.12 shall be of any
force or effect.

IN WITNESS WHEREOF, the parties have executed this Agreement in four
counterparts, two in English and two in Russian with one counterpart of each
language for each party. In the case of differences in interpretation between
the English and Russian texts of this Agreement, the English text shall control.

FIRST INVESTMENT VOUCHER FUND              PIONEER REAL ESTATE ADVISORS
                                           INC.

[SEAL]

/s/ Michael Yu Chebotarev                  /s/ Stephen G. Kasnet
----------------------------               -------------------------------------
Michael Yu Chebotarev                      Stephen G. Kasnet
Chairman Board of Directors                President
(Company Seal)                             (Company Seal)

Executed:                               Executed:
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