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                                 EXHIBIT 10.11

                    JOINT VENTURE PARTNERSHIP AGREEMENT OF

                 WELLS FUND XII-REIT JOINT VENTURE PARTNERSHIP
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                      JOINT VENTURE PARTNERSHIP AGREEMENT
                                      OF
                 WELLS FUND XII-REIT JOINT VENTURE PARTNERSHIP

     THIS JOINT VENTURE PARTNERSHIP AGREEMENT (the "Agreement") is made and
entered into as of the 10th day of April, 2000, by and between WELLS OPERATING
PARTNERSHIP, L.P., a Delaware limited partnership having Wells Real Estate
Investment Trust, Inc., a Maryland corporation, as general partner ("Wells OP"),
and WELLS REAL ESTATE FUND XII, L.P., a Georgia limited partnership having Leo
F. Wells, III and Wells Partners, L.P., a Georgia limited partnership, as
general partners ("Fund XII").  Each of the parties may also be referred to
herein as a "Venturer" and together as the "Venturers."

                             W I T N E S S E T H:
                             - - - - - - - - - -

     WHEREAS, the Venturers desire to form a partnership under the Georgia
Uniform Partnership Act for the acquisition, development, operation and sale of
real properties according to the terms and conditions set forth herein;

     NOW, THEREFORE, for and in consideration of the mutual covenants
hereinafter set forth, the parties hereto covenant and agree as follows:

     1.   DEFINITIONS.
          -----------

          For the purposes of this Agreement, the following defined terms shall
have the meanings ascribed thereto.

          1.1  "Administrative Venturer" means the Entity responsible for the
                -----------------------
conduct of the ordinary and usual business of the Venture and the implementation
of the decisions of the Venturers, all as is more fully set forth in Subsection
4.2 hereof. The initial Administrative Venturer shall be Wells OP.

          1.2  "Agreed Value" means with respect to Contributed Property the
                ------------
fair market value of such property as of the date of contribution to the Venture
as determined by the general partners of the Venturers.

          1.3  "Approve," "Approved" or "Approval" means, as to the subject
                -------    --------      --------
matter thereof and as the context may require, an express consent evidenced by
and contained in a written statement signed by the approving Entity.  A copy of
each such written statement shall be kept at the office of the respective
Venturer and shall be available for inspection by the other Venturer upon
request.

          1.4  "Bankrupt" or "Bankruptcy" means the occurrence of one or more of
                --------      ----------
the following events:
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          (i)   The appointment of a permanent or temporary receiver of the
assets and properties of the Venture or a Venturer, and the failure to secure
the removal thereof within 60 days after such appointment;

          (ii)  The adjudication of the Venture or a Venturer as bankrupt or the
commission by the Venture or a Venturer of an act of bankruptcy;

          (iii) The making by the Venture or a Venturer of an assignment for
the benefit of creditors;

          (iv)  The levying upon or attachment by process of the assets and
properties of the Venture or a Venturer; or

          (v)   The use by the Venture or a Venturer, whether voluntary or
involuntary, of any debt or relief proceedings under the present or future law
of any state or of the United States.

          1.5  "Capital Account" means a separate account maintained for each
                ---------------
Venturer in a manner which complies with Treasury Regulation Section 1.704-1(b),
as may be amended or revised from time to time.

          1.6  "Capital Contributions" means the aggregate contributions to the
                ---------------------
capital of the Venture made by the Venturers as Capital Contributions pursuant
to Subsection 3.1 hereof.

          1.7  "Contributed Property" means any property contributed to the
                --------------------
Venture as a Capital Contribution and/or the interest of each Venturer
contributing property (excluding cash or cash equivalents) to the Venture in
such property.

          1.8  "Defaulting Venturer" means any Venturer failing to perform any
                -------------------
of the obligations of such Venturer under this Agreement or violating the
provisions of this Agreement.

          1.9  "Distribution Percentage Interests" means collectively the
                ---------------------------------
interests in the income, gains, losses, deductions, credits, Net Cash Flow,
Extraordinary Receipts, as determined by Subsection 3.2 hereof, as such may be
adjusted from time to time as provided in this Agreement.

          1.10 "Entity" means any person, corporation, partnership (general or
                ------
limited), joint venture, association, joint stock company, trust or other
business entity or organization.

          1.11 "Extraordinary Receipts" means those funds of the Venture which
                ----------------------
are derived from (i) the net proceeds of any casualty insurance insuring any of
the Properties or any portion thereof, to the extent not applied to the repair,
restoration or replacement of the Properties or any portion thereof as

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may be Approved by the Venturers; (ii) the net proceeds of any condemnation, or
any taking by eminent domain, or any transfer in lieu thereof, of any of the
Properties, or any portion thereof, to the extent not applied to the repair,
restoration or reconstruction of any remaining portion of the Properties as may
be Approved by the Venturers; (iii) the net proceeds of any sale of any of the
Properties, or any portion thereof; and (iv) the net proceeds of any
indebtedness (or any refinancing of such indebtedness) secured in whole or in
part by any of the Properties or any portion thereof.

          1.12 "Fiscal Year" means the fiscal year of the Venture established
                -----------
under Subsection 3.4(c) hereof.

          1.13 "I.R.C." means the Internal Revenue Code of 1986, as amended.
                ------

          1.14 "Lease" means a lease or rental agreement now or hereafter
                -----
existing between the Venture, as lessor or landlord (whether initially or by
assignment) and an Entity.

          1.15 "Leasing Agreements" means, collectively, those certain Leasing
                ------------------
and Tenant Coordinating Agreements between the Venturers as "Owner" and Wells
Management Company, Inc. as "Agent" therein, concerning the leasing of the
Properties.

          1.16 "Major Decisions" means any decision or action to (i) convey by
                ---------------
the Venture substantially all the assets of the Venture; (ii) acquire any
Property; (iii) finance or borrow or execute any promissory note or other
obligation (other than a Lease) or mortgage or other encumbrance in the name of
or on behalf of the Venture; (iv) retain the services of a manager other than
Wells Management Company, Inc.; (v) approve each construction and architectural
contract and all architectural plans, specifications and drawings and all
revisions or changes thereof in connection with the development and construction
of any improvements for any Property; (vi) reduce any portion of the insurance
program for the Properties or the Venture; (vii) determine any fee or other
amount to be paid to either Venturer or any affiliate of a Venturer; (viii) make
any expenditure or incur any obligation by or on behalf of the Venture involving
a sum in excess of $15,000 for any transaction or group of similar transactions
except for expenditures made and obligations incurred pursuant to and
specifically set forth in a budget Approved by the Venturers; (ix) adjust,
settle or compromise any claim, obligation, debt, demand, suit or judgment
against the Venture or any Venturer in its capacity as a Venturer, or waive any
breach of or default in any monetary or non-monetary obligation owed to the
Venture, involving singly or in the aggregate an amount in excess of $15,000, or
in the initiation of any such claim or suit for the benefit of the Venture; (x)
convey or sell any Property or authorize the conveyance or sale of all
Properties; (xi) admit any new Venturer to the Venture; (xii) cause the Venture
to be

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admitted as a joint venturer to any other joint venture; and (xiii) make any
other decision or action which by the provisions of this Agreement is required
to be Approved by the Venturers or which in a material respect affects the
Venture or any of the assets or operations thereof. All Major Decisions shall be
made by the Venturers in a timely manner with due regard for the necessity of
obtaining and evaluating the information necessary for making such Major
Decisions.

          1.17 "Management Agreements" means, collectively, those certain
                ---------------------
Management Agreements between the Venturers as "Owner" and Wells Management
Company, Inc. as "Manager" therein, concerning the management of the Properties.

          1.18 "Manager" means Wells Management Company, Inc.
                -------

          1.19 "Net Cash Flow" means for a given fiscal period, those funds of
                -------------
the Venture constituting the gross cash receipts of the Venture from the
operation of the Properties (including interest and proceeds from business
interruption or rent insurance) for such period exclusive of Capital
Contributions by the Venturers and Extraordinary Receipts, which are available
for distribution to the Venturers following (i) the payment of all operating,
fixed cost and capital expenditures of the Venture, for which no reserves have
been established, applicable to such period; (ii) the payment of all principal
and interest with respect to any debt secured by any mortgage permitted by this
Agreement; and (iii) the establishment by the Venturers of appropriate reserves
for taxes, debt service, maintenance, repairs and other expenses and working
capital requirements of the Venture including, without limitation, accruals for
real estate taxes, insurance and other annual expense items (unless and to the
extent the same are escrowed with a mortgagee).

          1.20 "Nondefaulting Venturer" in the context wherein one or more
                ----------------------
Venturers become a Defaulting Venturer, means the remaining Venturers (provided
the remaining Venturers are not also Defaulting Venturers).

          1.21 "Notice" means a written advice or notification required or
                ------
permitted by this Agreement, as more particularly provided in Subsection 8.1
hereof.

          1.22 "Prime Rate" means the rate of interest announced from time to
                ----------
time by NationsBank, N.A. as its prime rate.  In the event the prime rate of
NationsBank, N.A. is hereafter discontinued or becomes unascertainable, the
Administrative Venturer shall designate a comparable reference rate to be the
Prime Rate.

          1.23 "Property" means any particular tract of land (and all rights
                --------
and appurtenances incident thereto) owned or to be owned by the Venture or owned
or to be owned by any joint venture, partnership, limited liability

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company or other entity in which the Venture owns an economic or beneficial
interest and all improvements located, constructed or developed thereon or to be
constructed or developed thereon.

          1.24 "Properties" means, collectively, all Property of the Venture at
                ----------
any given time.

          1.25 "Purchasing Party" means the Venturer other than the Selling
                ----------------
Party in the event of a proposed transfer described in Subsection 6.4 hereof.

          1.26 "Selling Party" means the Venturer desiring to transfer its
                -------------
interest in a transaction described in Subsection 6.4 hereof.

          1.27 "Venture" means the joint venture formed pursuant to the laws of
                -------
the State of Georgia by this Agreement.

          1.28 "Venturer" or "Venturers" means the party or parties to this
                --------      ---------
Agreement and all permitted successors and assigns thereof.

          1.29 Other terms defined in this Agreement:

               Term                          Section
               ----                          -------

               "Assignment"                  6.1
               "Right of First Refusal"      6.2
               "Certification"               6.4(a)
               "Accepting Venturer"          6.5(a)
               "Dissenting Venturer"         6.5(a)

     2.   THE VENTURE.
          -----------

          2.1  Formation.  The Venturers hereby enter into and form the Venture
               ---------
as a Georgia general partnership under the Georgia Uniform Partnership Act for
the limited purposes and scope set forth herein. The rights and obligations of
the Venturers and the status, administration and termination of the Venture
shall be governed by the Georgia Uniform Partnership Act and other applicable
laws of the State of Georgia. The Venture is being formed for the sole purpose
of acquiring, owning, developing, operating and eventually selling Properties.

          2.2  Purposes and Scope of Venture.  Subject to the provisions of this
               -----------------------------
Agreement, the activities of the Venture shall be limited strictly to the
acquisition, ownership, financing, development, leasing, operation, sale and
management of the Properties for the production of income and profit, either
directly or through the ownership of joint ventures, partnerships, limited
liability companies or other entities, including all activities reasonably

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necessary or desirable to accomplish such purposes, and shall not be extended by
implication or otherwise unless Approved by all venturers. Nothing in this
Agreement shall be deemed to restrict in any way the freedom of any Venturer to
conduct any other business or activity whatsoever (including, without
limitation, the acquisition, development, leasing, sale, operation and
management of other real property) without any accountability to the Venture or
any other Venturer, even if such business or activity competes with the business
of the Venture, it being understood by each Venturer that the other Venturer may
be interested directly or indirectly in various other businesses and
undertakings not included in the Venture.

          2.3  Name of Venture.  The business and affairs of the Venture shall
               ---------------
be conducted under the name the "Wells Fund XII-REIT Joint Venture Partnership"
(or such other names as shall be approved by both Venturers), and such name
shall be used at all times in connection with the business and affairs of the
Venture.  The Venturers shall execute any assumed or fictitious name certificate
or certificates required by law to be filed in connection with the formation of
the Venture and shall cause such certificate or certificates to be filed in the
appropriate records.

          2.4  Scope of Authority.  Except as otherwise expressly and
               ------------------
specifically provided in this Agreement, no Venturer shall have any authority to
act for, or assume any obligations or responsibility on behalf of, any other
Venturer or the Venture.

          2.5  Principal Place of Business.  The principal place of business and
               ---------------------------
initial office of the Venture shall be located at 6200 The Corners Parkway,
Suite 250, Norcross, Georgia 30092, and may be relocated as may be from time to
time Approved by the Venturers.

          2.6  Representations, Warranties and Indemnity.  In order to induce
               -----------------------------------------
the other Venturer to enter into this Agreement, each Venturer does hereby make
to each other Venturer the representations and warranties hereinafter set forth,
and does hereby agree to indemnify and hold each other Venturer harmless from
any and all loss, expense or liability any other Venturer may suffer as a result
of any inaccuracy as of the date hereof in any representation and warranty set
forth below:

               (a)  Authorization.  The execution and delivery of this Agreement
                    -------------
has been duly authorized by the agreements by which each Venturer was either
created or currently governed.

               (b)  Claims.  There is no claim, litigation, proceeding or
                    ------
governmental investigation pending, or, so far as is known to each Venturer,
threatened, against or relating to each Venturer, or the transactions
contemplated by this Agreement which does or would reasonably be expected

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materially and adversely to affect the ability of each Venturer to enter into
this Agreement or to carry out its obligations hereunder, and there is not any
basis for any such claim, litigation, proceeding or governmental investigation.

               (c)  Conflicts.  Neither the consummation of the transactions
                    ---------
contemplated by this Agreement to be performed, nor the fulfillment of the
terms, conditions and provisions of this Agreement, conflict with or will result
in the breach of any of the terms, conditions or provisions of, or constitute a
default under, the agreements by which each Venturer was created or is currently
governed or any material agreement, indenture, instrument or undertaking to
which each Venturer is a party.

               (d)  Investment Objectives.  The investment objectives of each
                    ---------------------
Venturer with respect to the Properties and the objectives of the Venture are:
(i) to maximize Net Cash Flow; (ii) to preserve, protect and return the
Venturers' investment in the Venture; and (iii) to realize appreciation upon the
sale of the Properties.

               (e)  Charges to the Venturer.  Neither Venturer will be charged,
                    -----------------------
directly or indirectly, more than once for the same services.

          2.7  Term of Venture.
               ---------------

               (a)  Commencement.  The Venture term shall begin on the date of
                    ------------
this Agreement as set forth above and end upon dissolution of the Venture.

               (b)  Dissolution and Termination.  Dissolution shall occur upon
                    ---------------------------
the occurrence of any of the events described in Section 7 of this Agreement.
Upon dissolution, the assets shall be liquidated in due course and distributed
as provided in Subsection 3.3(c)(i) hereof. The Venture shall continue until
termination in accordance with the relevant dissolution and termination
provisions of the Georgia Uniform Partnership Act.

     3.   FINANCIAL STRUCTURE.
          -------------------

          3.1  Capital Contributions.  The Venturers shall from time to time
               ---------------------
make Capital Contributions to the Venture in such amounts as are agreed to by
the Venturers.

          3.2  Distribution Percentage Interest.  The Distribution Percentage
               --------------------------------
Interest of each of the Venturers shall be equal to the percentage equivalent
(rounded to the nearest one-hundredth of a percent) of a fraction, the numerator
                                                                       ---------
of which is the aggregate of all Capital Contributions (or the Agreed Value
thereof) made by the Venturer pursuant to Subsection 3.1 hereof, and the
denominator of which is the aggregate amount of all Capital Contributions (or
-----------
the Agreed Value thereof) made by all of the Venturers

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pursuant to Subsection 3.1 hereof. Each Venturer's interest in the Venture shall
always be proportional to its Capital Contributions.

          Each Venturer (the "First Venturer") does hereby agree to indemnify
and hold the other Venturer (the "Second Venturer") harmless from and against
any claim, action, liability, loss, damage, cost or expense, including, without
limitation, attorney's fees and expenses incurred by the Second Venturer by
reason of (i) any act or omission of the First Venturer in connection with the
operation of the Venture and the Properties, or (ii) the claims made by third
parties to the extent that the Second Venturer's percentage share of the total
liability, loss, damage, cost or expense incurred by the Venture and the
Venturers in connection with such claims exceeds its Distribution Percentage
Interest at the time such liability, loss, damage, cost or expense is suffered
or incurred.  Upon dissolution, each Venturer shall look solely to the assets of
the Venture for the return of its investment, and if the Venture Property
remaining after payment or discharge of the debts and liabilities of the
Venture, including debts and liabilities owed to one or more of the Venturers,
is insufficient to return the aggregate Capital Contributions of each Venturer,
such Venturers shall have no recourse against the Venture or any other Venturer.

          3.3  Allocations and Distributions.  Allocations for accounting
               -----------------------------
purposes and for federal, state and local income tax purposes of each item of
income, loss, deduction and gain, and distributions of Net Cash Flow and
Extraordinary Receipts shall be allocated among the Venturers as follows:

               (a)  Allocation of Tax Items.  For federal, state and local
                    -----------------------
income tax purposes and for purposes of maintaining the Venturers' Capital
Accounts, except as otherwise provided herein, each item of income, gain, loss
and deduction of the Venture for each tax year shall be allocated to the
Venturers in accordance with their Distribution Percentage Interests.

               (b)  Net Cash Flow.  All distributions of Net Cash Flow shall be
                    -------------
made to the Venturers in accordance with each such Venturer's Distribution
Percentage Interest and shall be made at such intervals as may be approved by
the Venturers, but in no event less frequently than quarterly.

               (c)  Extraordinary Receipts.  Distributions of Extraordinary
                    ----------------------
Receipts shall be made as follows:

                    (i)  Distributions Not in Connection With Dissolution.
                         ------------------------------------------------
Distribution of Extraordinary Receipts not generated in connection with an event
of dissolution shall be made as follows: first, to the establishment of any
                                         -----
reserve approved by the Venturers; and second, to the Venturers based on their
                                       ------
respective Distribution Percentage Interests.

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                    (ii) Distributions in Connection With Dissolution.
                         --------------------------------------------
Distribution of Extraordinary Receipts generated in connection with an event of
dissolution (as well as the other assets of the Venture) shall be made as
follows: first, to the payment of debts and liabilities of the Venture to
         -----
creditors (including all mortgages, but excluding any other debts or liabilities
to Venturers or affiliates of Venturers), and to the expenses of liquidation;
second, to the establishment of such reserves as the Venturers may deem
------
reasonably necessary for contingent or unforeseen liabilities or obligations of
the Venture, which may be held in escrow for a reasonable period of time and
then distributed pursuant to the remainder of this Subsection; third, to the
                                                               -----
repayment of any remaining debts and obligations of the Venture to the Venturers
or affiliates of the Venturers; and fourth, to the Venturers in accordance with
                                    ------
the positive balances in their respective Capital Accounts.

               (d)  Compliance with Section 704(c).  To comply with Section
                    ------------------------------
704(c) of the I.R.C., items of income, gain, loss, depreciation and cost
recovery deductions attributable to Contributed Property shall be allocated for
federal income tax purposes among the Venturers in the manner provided under
Section 704(c) of the I.R.C. taking into account the variation, if any, between
the Agreed Value of such Property and its adjusted tax basis at the time of
contribution.

               (e)  Qualified Income Offset.  Notwithstanding any provision to
                    -----------------------
the contrary contained herein, in the event that any Venturer receives an
adjustment, allocation or distribution described in Treasury Regulations
Sections 1.704-1(b)(2)(ii)(d)(4), (5) or (6) which causes a deficit balance in
such Venturer's Capital Account, such Venturer will be allocated items of income
or gain (consisting of a pro rata portion of each item of partnership income,
including gross income, and gain for such year) in an amount and manner
sufficient to eliminate such deficit balance as quickly as possible, all in
accordance with Treasury Regulations Section 1.704-1(b)(2)(ii)(d).  (It is the
intent of the Venturers that the foregoing provision constitute a "Qualified
Income Offset," as defined in Treasury Regulations Section 1.704-1(b)(2)(ii)(d),
and the foregoing provision shall in all events be interpreted so as to
constitute a valid "Qualified Income Offset.")

          3.4  Income Taxes and Accounting.
               ---------------------------

               (a)  Income Tax Returns.  All income tax returns of the Venture
                    ------------------
shall be prepared on an accrual basis (except to the extent as may otherwise be
Approved by all Venturers or be required by law, statute or regulation governing
such tax and returns).

               (b)  Elections.  Any provision of this Agreement to the contrary
                    ---------
notwithstanding, solely for federal income tax purposes, each of the Venturers
hereby recognizes that the Venture will be subject to all provisions of

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Subchapter K of Chapter 1 of Subtitle A of the I.R.C.; provided, however, that
the filing of U.S. Partnership Returns of Income shall not be construed to
extend the purposes of the Venture or expand the obligations or liabilities of
the Venturers. The Venture shall file an election under Section 754 of the
I.R.C. only in the event of a transfer or proposed transfer by any one or more
Venturers of all or any part of their interest or interests in the Venture to
any Entity. Such election shall be filed by the Venture upon the request of any
Venturer made with respect to the income tax return for the period which
includes the date of transfer of such interest in the Venture; such request
shall be in writing and shall be made not less than 60 days prior to the initial
date established by law for filing such income tax return.

               (c)  Fiscal Year.  The Venture shall operate on a calendar year
                    -----------
basis.

               (d)  Books of Account.  The books of account of the Venture and
                    ----------------
the Venturer's Properties shall be kept and maintained at all times by the
Administrative Venturer or the delegated representative thereof at the principal
place of business of the Administrative Venturer. The books of account shall be
maintained on an accrual basis, unless otherwise determined by the
Administrative Venturer, in accordance with generally accepted accounting
principles, consistently applied, and shall show all items of income and expense
relating to the Venture and the Properties.

               (e)  Reports.  The Administrative Venturer shall cause to be
                    -------
prepared at the expense of the Venture and furnished to each of the Venturers
the information and data with respect to the Venture during the Fiscal Year as
shall enable each Venturer on a timely basis to prepare or cause to be prepared
the reports required under their respective partnership agreements to be made to
their partners. In addition, within 60 days after the end of each Fiscal Year,
the Administrative Venturer shall use its best efforts to cause to be prepared
and to deliver to each Venturer a report setting forth in sufficient detail all
such information and data with respect to business transactions effected by or
involving the Venture during such Fiscal Year as shall enable the Venture and
each Venturer to prepare its federal, state and local income tax returns on a
timely basis in accordance with the laws, rules and regulations then prevailing.
The Administrative Venturer shall cause to be prepared federal, state and local
tax returns required of the Venture and submit such returns to the Venturers no
later than 30 days prior to the date required for the filing thereof and shall
file the same.

               (f)  Records.  Any Venturer shall have the right at all
                    -------
reasonable times during usual business hours to audit, examine and make copies
of the books of account of the Venture. Such right may be exercised through any
agent or employee of such Venturer designated by such Venturer or by an
independent certified public accountant designated by such Venturer.

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<PAGE>

Any Venturer shall bear all expenses incurred in any examination or audit made
for such Venturer's account.

               (g)  Audits.  In the event that the Internal Revenue Service or
                    ------
any other governmental agency with jurisdiction shall conduct, commence or give
notification of intent to conduct or commence any audit or other investigation
of the books, records, tax returns or other affairs of the Venture, the
Administrative Venturer shall immediately advise the Venturers thereof by
Notice. The Administrative Venturer shall be the "tax matters partner," as that
term is defined by I.R.C., if one is needed for the Venture.

          3.5  Banking.  Funds of the Venture shall be deposited in an account
               -------
or accounts of a type, in form and name and in a bank or banks selected by the
Administrative Venturer. No funds other than Venture funds shall be deposited in
any such account. Withdrawals from bank accounts shall be made by the
Administrative Venturer and by such other parties as may be designated by the
Venturers.

     4.   MANAGEMENT.
          ----------

          4.1  Authority of Administrative Venturer.  The overall management and
               ------------------------------------
control of the business and affairs of the Venture shall be vested in the
Venturers, collectively, acting by and through the Administrative Venturer. The
Administrative Venturer shall have responsibility for establishing the policies
and operating procedures with respect to the business and affairs of the Venture
and for making all decisions, except as otherwise provided herein and except
Major Decisions, as to all matters which the Venture has authority to perform,
as fully as if the Venturers were themselves making such decisions. All
decisions, other than Major Decisions, with respect to the management and
control of the Venture made by the Administrative Venturer shall be binding on
the Venture and all Venturers. The Administrative Venturer shall be responsible
for performing, or for causing to be performed, all acts necessary to accomplish
the purposes of the Venture. No act shall be taken, sum expended, decision made
or obligation incurred by the Venture, or any Venturer, with respect to a matter
within the scope of any of the Major Decisions, unless such matter has been
Approved by all of the Venturers. Except as otherwise expressly provided for in
this Agreement, documents executed by or behalf of the Venture shall be executed
only with the Approval of the Administrative Venturer.

          4.2  Administrative Venturer.  The initial Administrative Venturer
               -----------------------
shall be Wells OP. The Administrative Venturer shall, at the expense of the
Venture, discharge or cause the discharge of the duties of the Administrative
Venturer unless and until (i) the Administrative Venturer resigns as the
Administrative Venturer, or (ii) the Administrative Venturer becomes a
Defaulting Venturer. In the event of an occurrence described in either clause

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(i) or (ii) of the immediately preceding sentence, the then current
Administrative Venturer shall thereupon be relieved from any further performance
of the functions of the Administrative Venturer under this Agreement and a
replacement for the Administrative Venturer shall be appointed by a majority in
interest of the other Venturers. In the event an Entity not a Venturer shall be
appointed to be Administrative Venturer, such Entity shall discharge the
functions of the Administrative Venturer under this Agreement but shall not be
entitled to any of the rights, titles or interests of a Venturer. The breach or
violation by the Administrative Venturer of any provision of this Subsection, or
of any other duty or obligation imposed upon the Administrative Venturer by this
Agreement, shall subject to the Administrative Venturer to the provisions of
Subsection 4.4 hereof as a Defaulting Venturer (provided the Administrative
Venturer is then also a Venturer) only if such breach or violation by the
Administrative Venturer involves fraud, negligence or willful misconduct.
Furthermore, the Administrative Venturer shall be liable to the Venture and to
the Venturers for any breach or violation of the Administrative Venturer's
duties and obligations under this Subsection only if such breach or violation
involves fraud, negligence or willful misconduct.

               (a)  Records.  The Administrative Venturer shall maintain or
                    -------
cause to be maintained at the expense of the Venture, books of account as
described in Subsection 3.4(d) hereof.

               (b)  Property Taxes and Licenses.  The Administrative Venturer
                    ---------------------------
shall cause to be filed each year timely ad valorem tax returns for the
Properties.

               (c)  Leases.  The Administrative Venturer is authorized to
                    ------
negotiate and execute Leases on behalf of the Venture without further Approval
of the Venturers and is authorized to delegate this responsibility pursuant to a
management agreement. Initially, this responsibility will be delegated to the
Manager under the Management Agreements and Leasing Agreements by and between
the Venturers and the Manager.

               (d)  Indemnity.  The Venture shall indemnify and hold the
                    ---------
Administrative Venturer harmless against all claims, actions, liability, loss,
damage, cost or expense, including attorney's fees and expenses, by reason of
any act or omission of the Administrative Venturer that is duly authorized and
performed in accordance with the terms and provisions of this Agreement.
However, any Entity which is both the Administrative Venturer and a Venturer
shall be responsible as a Venturer, to the extent of the proportionate liability
thereof, for such obligation for the Venture to so indemnify and hold harmless
the Administrative Venturer. The liability of the Venturers under this
Subsection shall be several, and not joint, and shall be shared in proportion to
the Distribution Percentage Interests of the Venturers.

                                       12
<PAGE>

          4.3  Compensation of Venturers.  No payment will be made by the
               -------------------------
Venture to any Venturer for the services of such Venturer or any affiliate,
partner or employee of any Venturer, other than as provided in the Management
Agreements and the Leasing Agreements.

          4.4  Defaulting Venturer.  If any Venturer fails to perform any of its
               -------------------
obligations under this Agreement or violates the terms of this Agreement, such
Venturer shall be a Defaulting Venturer and the Nondefaulting Venturer shall
have the right to give such Defaulting Venturer a Notice specifically setting
forth the nature of the default and stating that such Defaulting Venturer shall
have a period of 15 days to pay any sums of money specified therein as due and
owing to the Venture or to any Venturer, or 30 days (or such longer period as is
specified in the next succeeding sentence) to cure any other default specified
in such Notice. If the monies specified are not paid within such 15 day period
or such Defaulting Venturer does not cure all other defaults within such 30 day
period, or, if the defaults are not capable of being cured within such 30 day
period, such Defaulting Venturer has not commenced in good faith the curing of
such defaults within such 30 days period and does not thereafter prosecute to
completion with diligence and continuity the curing thereof, the Nondefaulting
Venturer shall have all rights provided in Subsections 4.4(a) through 4.4(c)
below, in addition to any other rights it may have under the Georgia Uniform
Partnership Act. If a Defaulting Venturer completely cures all of such defaults
within the aforesaid cure periods, then such defaults shall be deemed no longer
to exist and such Venturer shall be deemed no longer to constitute a Defaulting
Venturer unless and until another default by such Venturer occurs. A Defaulting
Venturer shall have no power or authority to bind the Venture or the Venturers
but shall cooperate with and, to the extent requested, assist the Nondefaulting
Venturers in every way possible.

               (a)  Equitable Relief.  The Nondefaulting Venturer may bring any
                    ----------------
proceeding in the nature of injunction, specific performance or other equitable
remedy, it being acknowledged by each of the Venturers that damages at law may
be an inadequate remedy for a default or threatened breach of this Agreement.

               (b)  Damages.  The Nondefaulting Venturer may bring any action
                    -------
at law by or on behalf of itself or the Venture as may be permitted in order to
recover damages.

               (c)  Dissolution.  The Nondefaulting Venturer may institute such
                    -----------
proceedings as may be appropriate to secure an accounting and to dissolve, wind
up and terminate the Venture.

               (d)  Additional Remedies.  The rights and remedies of the
                    -------------------
Venturers under this Agreement shall not be mutually exclusive; that is, the

                                       13
<PAGE>

exercise of one or more of the provisions hereof shall not preclude the exercise
of any other provisions hereof, except as may be expressly provided in this
Agreement. Each of the Venturers confirms that damages at law may be an
inadequate remedy for a breach or threatened breach of this Agreement and agrees
that, in the event of a breach or threatened breach of any provision hereof, the
respective rights and obligations hereunder shall be enforceable by specific
performance, injunction or other equitable remedy, but nothing herein contained
is intended to, nor shall it, limit or affect any right or rights at law or by
statute or otherwise of any Venturer aggrieved as against any other Venturer for
breach or threatened breach of any provisions of this Agreement, it being the
intention of this Subsection to make clear the Agreement of the Venturers that
the respective rights and obligations of the Venturers under this Agreement
shall be enforceable in equity as well as at law or otherwise.

          4.5  Limitation on Authority.  Notwithstanding any provision of this
               -----------------------
Agreement to the contrary, neither Venturer shall have the authority to take any
action which, if taken singularly by such Venturer separate from the Venture,
would be prohibited by such Venturer's

          4.6  Holding Title as Nominee.  With the consent of the other
               ------------------------
Venturers, any Venturer shall be authorized to hold title to a Property or
Properties as agent or as nominee on behalf of the Venture.

     5.   INSURANCE.
          ---------

          5.1  Minimum Insurance Requirements.  The Venture shall carry and
               ------------------------------
maintain in force the insurance hereinafter described, the premiums for which
shall be a cost and expense of the Venture.

               (a)  Liability Insurance.  Comprehensive general liability
                    -------------------
insurance for the benefit of the Venture and the Venturers as named insureds
against claims for "personal injury" liability.

               (b)  Other Insurance.  Such other insurance as the Venturers may
                    ---------------
reasonably deem to be necessary or as may be required by any mortgagee of any
Property of the Venture.

          5.2  Insureds.  All of the policies of insurance described in
               --------
Subsection 5.1 shall name the Venture and each of the Venturers as named
insureds, as their respective interests may appear.  All such insurance shall be
effected under policies issued by insurers and be in forms and for amounts
Approved by both Venturers.

     6.   TRANSFERS AND OTHER DISPOSITIONS.
          --------------------------------

          6.1  Prohibited Transfers.  No Venturer may sell, transfer, assign,
               --------------------
mortgage, pledge, hypothecate or otherwise dispose of, encumber or permit or

                                       14
<PAGE>

suffer any encumbrance on (all referred to as "Assignment"), all or any part of
the interest of such Venturer in the Venture or in the Properties (including,
but not limited to, the right to receive any distributions under this Agreement)
unless such an Assignment is Approved by all Venturers, provided that this
restriction on Assignment shall not apply to the Assignment of units of
partnership interests or beneficial interests in a Venturer. Any Assignment made
in violation of this Section 6 shall be void.

          6.2  Exceptions.  The prohibition in Subsection 6.1 hereof shall not
               ----------
apply to:  (a) an Assignment permitted under Subsection 6.4 hereof ("Right of
First Refusal").

          6.3  Notice.  Each Venturer shall promptly by Notice inform the other
               ------
Venturer of the occurrence of any disposition not required to have been Approved
by the other Venturer.

          6.4  Right of First Refusal.  If any Selling Party shall desire to
               ----------------------
transfer (for the purposes of this Subsection the terms "transfer" and
"transferred" include any and all types of disposition) all or any portion of
its interest in the Venture to any Entity, such Selling Party may consummate
such transfer only if (i) such sale is a sale of Selling Party's interest in the
Venture separate and distinct from any other property, (ii) the consideration
payable is cash and/or note(s) and not an interest in other property, and (iii)
the provisions and conditions of Subsections (a) through (d) hereof have been
complied with.

               (a)  Certification.  The Selling Party shall deliver to the
                    -------------
Purchasing Party a written certification ("Certification") reflecting (i) the
name of the prospective transferee of the entire interest of the Selling Party
in the Venture; (ii) the price for which, and the terms upon which, the Selling
Party is willing to transfer and such prospective transferee is willing to buy
the entire interest of the Selling Party in the Venture (which price and terms
shall be based either upon preliminary discussions and negotiations, evidenced
in a writing signed by the prospective transferee, between the Selling Party and
such prospective transferee or upon a fully negotiated and executed purchase
agreement, a copy of which shall be furnished to the Purchasing Party); and
(iii) whether the Selling Party has any interest, financial or otherwise, in the
prospective transferee and whether, to the best knowledge of the Selling Party,
there exists any other contract or offer for the purchase of all or any portion
of the Properties or of the Selling Party's interest in the Venture. Such
Certification shall be accompanied by a request (in the form of a Notice) by the
Selling Party to the Purchasing Party to either Approve such transfer and
prospective transferee or to purchase the Selling Party's interest in the
Venture for the price and upon the terms provided in such Certification. The
Selling Party may transfer the interest of the Selling Party in the Venture only
to such prospective transferee or to the Purchasing Party. The Purchasing Party
must

                                       15
<PAGE>

either approve such prospective transferee or purchase the interest of the
Selling Party in the Venture.

               (b)  Purchasing Party's Rights.  The Purchasing Party shall have
                    -------------------------
the right either (i) to allow the Selling Party to transfer the interest of the
Selling Party in the Venture for a price and upon terms no more favorable to the
prospective transferee than those reflected, and to the prospective transferee
named in the Certification, or (ii) to purchase the Selling Party's entire
interest in the Venture at the price contained in the Certification and on the
other terms and conditions of the Certification. The price for which, and the
terms upon which, the Selling Party shall transfer its interest in the Venture
shall, by way of illustration and not limitation, be deemed "more favorable"
than those reflected in the Certification if (i) the total actual transfer price
is lower than that set forth in such Certification, (ii) a lesser portion of the
price is paid in cash at the time of the transfer than that set forth in such
Certification, or (iii) the portion of the price not paid in cash at the time of
the transfer is payable over a longer period of time, at a lower interest rate
or with lower or less frequent periodic payments than those set forth in such
Certification.

               (c)  Notice of Election.  The Purchasing Party shall have a
                    ------------------
period of 60 days after receipt of the Selling Party's Certification specified
in Subsection 6.4(a) hereof to serve upon the Selling Party a Notice which shall
specify whether such Purchasing Party will Approve a transfer to such
prospective transferee, or whether the Purchasing Party shall purchase the
entire interest of the Selling Party as provided in Subsection 6.4(b) hereof. If
the Purchasing Party fails to give such Notice within the allocated time, the
Purchasing Party shall be deemed to have approved the transfer of the interest
to such prospective transferee, and the Purchasing Party shall, if requested by
the Selling Party, execute, acknowledge and deliver such documents, or cause the
same to be executed, acknowledged and delivered, including without limitation,
the rights and restrictions contained in this Section 6 with respect to further
transfers. Any such new Venturer shall execute and deliver to the other
Venturers such documents as the other Venturers may reasonably request
confirming the assumption by such new Venturer of the obligations of the Selling
Party under this Agreement. At the time of closing of a transfer to a third
party transferee pursuant to this Subsection 6.4, the Purchasing Party shall
execute and deliver to the Selling Party and such transferee a written estoppel
certificate in recordable form pursuant to which the Purchasing Party shall
certify and agree that to the best of the Purchasing Party's knowledge and
belief the pending transfer is permitted pursuant to this Subsection (provided,
that to the best of the Purchasing Party's knowledge and belief such transfer
is, in fact, permitted by this Subsection). In such estoppel certificate, the
Purchasing Party shall waive any further right whatsoever to attempt to force a
rescission or setting aside of such transfer; provided, however, the Purchasing
Party shall expressly reserve any rights thereafter to pursue any action for

                                       16
<PAGE>

damages against both the Selling Party and the transferee should the Purchasing
Party thereafter determine that, contrary to the Purchasing Party's earlier best
knowledge and belief, the transfer was in fact not consummated in strict
accordance with the terms of this Section 6.

               (d)  Power of Attorney.  In the event that either (i) the
                    -----------------
Purchasing Party shall have failed to respond, in the manner and within the time
required by Subsection 6.4(c) hereof, to the Selling Party's Certification
specified in Subsection 6.4(a) hereof, or (ii) the Purchasing Party shall have
served upon the Selling Party a Notice specifying that the Purchasing Party has
approved a transfer to a prospective transferee of the Selling Party as
contemplated by Subsection 6.4(c) hereof, and the Purchasing Party shall have
thereafter failed or refused, within ten days after receipt of a Notice from the
other Venturer requesting same, to execute, acknowledge and deliver such
documents, or cause the same to be done, as shall be required to effectuate a
transfer of such interest in accordance with the Certification, then, and in
either of such events, the Selling Party may execute, acknowledge and deliver
such documents for, on behalf of and in the stead of the Purchasing Party, and
such execution, acknowledgment and delivery by the Selling Party shall be for
all purposes as effective against and binding upon the Purchasing Party as
though such execution, acknowledgment and delivery had been by the Purchasing
Party; provided, however, that no such documents executed by the Selling Party
shall contain any undertaking on behalf of the Purchasing Party beyond the scope
of the undertakings necessary for the Selling Party to effectuate such transfer.
Each Venturer does hereby irrevocably constitute and appoint each other Venturer
as the true and lawful attorney in fact of such Venture and the successors and
assigns thereof, in the name, place and stead of such Venturer or the successors
or assigns thereof, as the case may be, to execute, acknowledge and deliver such
documents in the event such Venturer shall be the Purchasing Party under the
circumstances contemplated by this Subsection 6.4(d). It is expressly
understood, intended and agreed by each Venturer, for such Venturer and the
successors and assigns thereof, that the grant of the power of attorney to each
other Venturer pursuant to this Subsection 6.4(d) is coupled with an interest,
is irrevocable and shall survive the death, termination or legal incompetency of
such granting Venturer, as the case may be, or the assignment of the interest of
such granting Venturer in the Venture, or the dissolution of the Venture.

     6.5  Offer from Third Party to Purchase the Property.
          -----------------------------------------------

          (a)  In the event that one of the Venturers receives a bona fide offer
from an unrelated third party for the sale of all or substantially all of the
Properties or last remaining Property owned by the Venture at the time of such
offer, which offer such Venturer wishes to accept (the "Accepting Venturer"),
but the other Venturer wishes to reject, the Venturer not desiring to sell the
Property or Properties pursuant to said offer (the "Dissenting Venturer") must

                                       17
<PAGE>

elect within thirty (30) days after receipt by the Dissenting Venturer of notice
of said offer from the Accepting Venturer to either (i) purchase the Accepting
Venturer's entire interest in the Venture on the same terms and conditions as
the third party offer to purchase; or (ii) consent to the sale of the Properties
or last remaining Property of the Venturer pursuant to such third party offer.
The Accepting Venturer shall deliver to the Dissenting Venturer a written notice
(the "Notice") reflecting (i) the name and address of the person or entity
desiring to purchase the Properties or last remaining Property of the Venture;
(ii) the sales price to be paid by such person or entity; and (iii) shall
include a copy of the third party offer. In the event that the Dissenting
Venturer elects to purchase the Accepting Venturer's entire interest in the
Venture, the purchase price payable for the Accepting Partner's interest in the
Venture shall be equal to the amount such Accepting Venturer would have received
if the Property or Properties had been sold to such unrelated third party in
accordance with the terms of its offer, after payment of all sales commissions
and other fees and expenses which would have been due and payable upon the sale
of said Property or Properties and the repayment of all debts of the Venture, if
any.

          (b)  As set forth above, the Dissenting Venturer shall have 30 days
after receipt of the Notice in which to make its election. The election of the
Dissenting Venturer shall be made by written notice to the Accepting Venturer.
In the event that the Dissenting Venturer elects to purchase the Accepting
Venturer's interest in the Venture pursuant to alternative (i) above, the
Dissenting Venturer shall have an additional 30 days following the receipt of
the Notice within which to close the purchase of the Accepting Venturer's
interest in the Venture. The failure of the Dissenting Venturer to either elect
to purchase the Accepting Venturer's interest in the Venture pursuant to
subparagraph (a)(i) above within 30 days after the receipt by the Dissenting
Venturer of the Notice, or the failure to close the purchase of the Accepting
Venturer's interest in the Venture within the foregoing time period shall be
conclusively deemed to constitute a consent to the sale of the Properties or
last remaining Property of the Venturer pursuant to such third party offer.

          (c)  The closing of any purchase and sale under this Section 6.5 shall
be held at the principal office of the Venturer or at such other place as shall
be mutually agreed to by the Venturers within 30 days following the receipt by
the Accepting Venturer of written notice that the Dissenting Venturer has
exercised its option to purchase the Accepting Venturer's interest in the
Venture. At the closing, an appropriate assignment of the Accepting Venturer's
interest in the Venture, with covenants against Assignor's acts, together with
such other instruments and documents as may be necessary or appropriate to
effect the transfer of the Accepting Venturer's interest in the Venture, shall
be executed and delivered. The Venturers shall also execute and deliver an
amendment to this Agreement, if appropriate. The purchase price payable to the
Accepting Venturer shall be paid at closing by wire transfer of immediately
available federal funds. Effective the date of closing, the Accepting Venturer

                                       18
<PAGE>

shall cease to be a member of the Venture, and the Accepting Venturer shall have
no further rights, duties or obligations with respect to the Venture arising out
of this Agreement. Subsequent to the closing date, the Accepting Venturer shall
have no further interest in the Venture's capital, income, profits, losses,
gains, allocations or distributions.

          (d)  Upon any default or breach of any provision of this Section 6.5,
the nonbreaching party shall be entitled to sue such defaulting party and
recover damages or enforce the terms hereof by specific performance.

          (e)  In the event that either (i) the Dissenting Venturer shall have
failed to respond, in the manner and within the time required by Subsection
6.5(a) hereof, to the Accepting Venturer's Notice specified in Subsection 6.5(a)
hereof, or (ii) the Dissenting Venturer shall have served upon the Accepting
Venturer a notice specifying its intent to approve the transfer of the
Properties or Property, and the Dissenting Venturer shall have thereafter failed
or refused within ten (10) days after receipt of a notice from the Accepting
Venturer requesting same to execute, acknowledge and deliver such documents,
instruments and writings, or to cause the same to be done, as required to
effectuate the contemplated sale of the Properties, or (iii) the Dissenting
Venturer shall have failed to close the purchase of the Accepting Venturer's
interest in the Venture within the time period set forth in Subsection 6.5(c)
hereof, then, in such event, the Accepting Venturer may execute, acknowledge and
deliver such documents, instruments and writings for, and on behalf of, and in
the name, place and stead of, the Dissenting Venturer, and such execution,
acknowledgment and delivery by such Accepting Venturer shall be for all purposes
as effective against and binding upon the Venture and the Dissenting Venturer as
if such execution, acknowledgment and delivery had been made by the Dissenting
Venturer; provided, however, that no such documents executed by the Accepting
Venturer pursuant to the terms hereof shall contain any undertaking on behalf of
the Dissenting Venturer beyond the scope of the undertaking as necessary for the
Accepting Venturer to effectuate the transfer and sale of the Properties of the
Venture. Each Venturer does hereby irrevocably constitute and appoint each other
Venturer as its true and lawful attorney-in-fact of such Venturer and its
successors and assigns, in the name, place and stead of such Venturer or its
successors or assigns, as the case may be, to execute, acknowledge and deliver
any and all such deeds, assignments, documents, instruments and writings in the
event such Venturer shall be the Dissenting Venturer under the circumstances
contemplated by this Subsection 6.5(e). It is expressly understood, intended and
agreed by each Venturer, for such Venturer and its successors and assigns, that
the grant of the power of attorney to each other Venturer pursuant to this
Subsection 6.5(e) is coupled with an interest, is irrevocable and shall survive
the death, termination or legal incompetence of such granting Venturer, as the
case may be, or the assignment of the interest of such granting Venturer in the
Venture, or the dissolution of the Venture.

                                       19
<PAGE>

     7.   DISSOLUTION AND TERMINATION.
          ---------------------------

          The Venture shall dissolve on December 31, 2030, or upon the
occurrence of any of the following:

          (i)   A decree of a court of competent jurisdiction declaring
dissolution;

          (ii)  Sale of all or substantially all of the assets of the Venture
and the receipt and distribution of the proceeds therefrom;

          (iii) The Venture or either Venturer is adjudicated insolvent or
bankrupt;

          (iv)  Termination of either of the Venturers; or

          (v)   Unanimous consent of the Venturers.

Upon the occurrence of any of the events set forth in this Section 7, Notice
thereof shall be given to all of the Venturers by the Administrative Venturer
and the Administrative Venturer shall, as required by Subsection 2.7(b) hereof,
proceed to terminate and wind up the Venture and shall distribute the
Extraordinary Receipts (and the other assets of the Venture) resulting therefrom
in accordance with Subsection 3.3(c) hereof.

     8.   MISCELLANEOUS PROVISIONS.
          ------------------------

          8.1   Notices.  Notices given under this Agreement shall be in writing
                -------
and shall be deemed to have been properly given or served by the deposit of such
with the United States Postal Service, or any official successor thereto,
designated as registered or certified mail, return receipt requested, bearing
adequate postage and addressed as hereinafter provided. The time period in which
a response to any such Notice must be given or any action taken with respect
thereto, however, shall commence to run from the date of receipt on the return
receipt of the Notice. Rejection or other refusal to accept or the inability to
deliver because of changed address or status of which no Notice was given to the
Administrative Venturer shall be deemed to be receipt of the Notice sent. In the
event that registered or certified mail is not being accepted for prompt
delivery, each Notice may then be served by personal service addressed as
hereinafter provided. By giving to the other Venturer at least 30 days' Notice
thereof, any Venturer shall have the right from time to time during the term of
this Agreement to change his Notice address(es) and to specify as his Notice
address(es) any other address(es) within the continental United States of
America. Each Notice to the Venturers shall be sent to the addresses set forth
below (unless such Notice address is properly changed):

                       Wells Operating Partnership, L.P.

                                       20
<PAGE>

                           6200 The Corners Parkway
                                   Suite 250
                            Norcross, Georgia 30092

                       Wells Real Estate Fund XII, L.P.
                           6200 The Corners Parkway
                                   Suite 250
                            Norcross, Georgia 30092

          8.2  Governing Law.  This Agreement and the obligations of the
               -------------
Venturers hereunder shall be interpreted, construed and enforced in accordance
with the laws of the State of Georgia, including the Georgia Uniform Partnership
Act.

          8.3  Fees and Commissions.  Except as may otherwise be provided
               --------------------
herein, each Venturer hereby represents to each other Venturer that there are no
claims for brokerage or other commissions or finder's or other similar fees in
connection with the transactions contemplated by this Agreement insofar as such
claims shall be based on arrangements or agreements made by or on behalf of the
Venturer so representing, and each Venturer so representing hereby indemnifies
and agrees to hold harmless each other Venturer from and against all
liabilities, cost, damages and expenses from any such claims.

          8.4  Waiver.  No consent or waiver, express or implied, by any
               ------
Venturer to or of any breach or default by any other Venturer in the performance
by such other Venturer of the obligations thereof under this Agreement shall be
deemed or construed to be a consent or waiver to or of any other breach or
default in the performance by such other Venturer of the same or any other
obligations of such other Venturer under this Agreement. Failure on the part of
any Venturer to complain or any act or failure to act of any other Venturer or
to declare any other Venturer in default, irrespective of how long such failure
continues, shall not constitute a waiver of such Venturer of the rights thereof
under this Agreement.

          8.5  Severability.  If any provision of this Agreement or the
               ------------
application thereof to any Entity or circumstances shall be invalid or
unenforceable to any extent, the remainder of this Agreement and the application
of such provisions to any other Entity or circumstance shall not be affected
thereby and shall be enforced to the greatest extent permitted by law.

          8.6  Status Reports.  Recognizing that each Venturer may find it
               --------------
necessary from time to time to establish to third parties such as accountants,
banks, mortgagees or the like, the then current status of performance hereunder,
upon the written request of any other Venturer, made from time to time by
Notice, each Venturer shall furnish promptly a written statement (in

                                       21
<PAGE>

recordable form, if requested) on the status of any matter pertaining to this
Agreement to the best of the knowledge and belief of the Venturer making such
statement.

          8.7  Entire Agreement - Amendment.  This Agreement constitutes the
               ----------------------------
entire agreement of the Venturers with respect to the subject matter hereof.
Neither this Agreement nor any provision hereof may be changed, waived,
discharged or terminated orally, but only by an instrument in writing signed by
the Venturer against whom enforcement of the change, waiver, discharge or
termination is sought. The execution of any amendment to this Agreement, or the
execution of any other agreement or amendment thereto, by all Venturers shall
establish that such execution was made in accordance with any applicable
requirements for Approval.

          8.8  Terminology.  All personal pronouns used in this Agreement,
               -----------
whether used in the masculine, feminine or neuter gender, shall include all
other genders; the singular shall include the plural; and the plural shall
include the singular. Titles of Sections, Subsections and Paragraphs in this
Agreement are for convenience only, and neither limit nor amplify the provisions
of this Agreement, and all references in this Agreement to Sections, Subsections
or Paragraphs shall refer to the Section, Subsection or Paragraph of this
Agreement unless specific reference is made to another document or instrument.

          8.9  Counterparts.  This Agreement may be executed in any number of
               ------------
counterparts, each of which shall be deemed to be an original and all of which
together shall comprise but a single instrument.

          8.10 Successors and Assigns.  Subject to the restrictions on transfers
               ----------------------
and encumbrances set forth herein, this Agreement shall inure to the benefit of
and be binding upon the Venturers and their respective heirs, executors, legal
representatives, successors and assigns. Whenever in this Agreement a reference
to any Entity or Venturer is made, such reference shall be deemed to include a
reference to the heirs, executors, legal representatives, successors and assigns
of such Entity or Venturer.

     IN WITNESS WHEREOF, the undersigned Venturers have executed and entered
into this Joint Venture Partnership Agreement of Wells Fund XII-REIT Joint
Venture Partnership as of the day and year first above written.

                                    WELLS OPERATING PARTNERSHIP, L.P.
                                    A Delaware Limited Partnership

Signed, sealed and delivered        By: Wells Real Estate Investment Trust, Inc.
in the presence of:                     A Maryland Corporation
                                        (As General Partner)

                                       22
<PAGE>

/s/ Douglas P. Williams
-------------------------------
Unofficial Witness

/s/ Martha Jean Cory                    By:  /s/ Leo F. Wells
-------------------------------              ---------------------------------
Notary Public                                Leo F. Wells, III
                                             President


                                   WELLS REAL ESTATE FUND XII, L.P.
                                   A Georgia Limited Partnership

                                   By:  Wells Partners, L.P.
                                        A Georgia Limited Partnership
                                        (As General Partner)
Signed, sealed and delivered
in the presence of:                     By:  Wells Capital, Inc.
                                             A Georgia Corporation
/s/ Douglas P. Williams                      (As General Partner)
-------------------------------
Unofficial Witness

/s/ Martha Jean Cory                    By:  /s/ Leo F. Wells
-------------------------------              ---------------------------------
Notary Public                                Leo F. Wells, III
                                             President


Signed, sealed and delivered       By:  /s/ Leo F. Wells
                                        --------------------------------------
in the presence of:                     Leo F. Wells, III
                                        General Partner

/s/ Douglas P. Williams
-------------------------------
Unofficial Witness

/s/  Martha Jean Cory
-------------------------------
Notary Public

                                      23