Document:

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                                             EXHIBIT NUMBER (10)(xxix)(1)
                                             TO 2000 FORM 10-K

                           FIRST AMENDMENT TO LEASE

           THIS FIRST AMENDMENT TO LEASE (this "Amendment"), made and entered
into as of the 29 day of February, 2000, by and between PERIMETER SUMMIT PARCEL
               --
3 LIMITED PARTNERSHIP, a Georgia limited partnership ("Landlord") and NORTHERN
TRUST RETIREMENT CONSULTING, LLC, a Delaware limited liability corporation
("Tenant").

                                WITNESSETH THAT:

           WHEREAS, Landlord and Tenant entered into that certain Lease
Agreement dated November 5, 1999 (the "Lease"), for certain premises in the
building located at 3003 Summit Boulevard, Atlanta, Georgia (the "Building"),
consisting of approximately 127,611 rentable square feet of space (the
"Premises");

           WHEREAS, Landlord and Tenant desire to amend the Lease and other
matters by means of this Amendment.

           NOW THEREFORE, in consideration of the mutual covenants contained
herein, and other good and valuable consideration, the receipt, adequacy and
sufficiency of which are hereby acknowledged, the Lease is hereby amended and
the parties hereto do hereby agree as follows:

           1.  Landlord hereby agrees to provide to Tenant an additional tenant
               improvement allowance equal to $2.66 per rentable square foot of
               space (the "Supplemental Tenant Improvement Allowance") with
               respect to the initial Premises and any other premises leased by
               Tenant having a term that commences upon the Commencement Date or
               within one hundred eighty (180) days after such Commencement Date
               which shall include Tenant's Expansion Option A and Expansion
               Option B under Expansion Schedule I of the Lease. The
               Supplemental Tenant Improvement Allowance shall be considered
               part of the Tenant Improvement Allowance for all purposes under
               the Lease and may be utilized by Tenant for Construction Costs,
               other tenant improvement costs or as an offset against Base
               Rental until fully utilized.

           2.  All capitalized terms used herein and not otherwise defined
               herein shall have the meanings ascribed to them in the Lease.

           EXCEPT AS expressly amended and modified hereby, the Lease shall
otherwise remain in full force and effect, the parties hereto hereby ratifying
and confirming the same. To the extent of any inconsistency between the Lease
and this Amendment, the terms of this Amendment shall control.
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      IN WITNESS WHEREOF, the undersigned parties have duly executed this
      Amendment as of the day and year first above written.

LANDLORD:                                   TENANT:

PERIMETER SUMMIT PARCEL 3                   NORTHERN TRUST RETIREMENT
LIMITED PARTNERSHIP, a Georgia              CONSULTING, LLC, a Delaware limited
limited partnership                         liability corporation

By: Hires Management, L.L.C., a Delaware    By:         /s/Dennis Sain
    limited liability company, general          ----------------------
    partner of Perimeter Summit Parcel 3         Name: Dennis Sain
    Limited Partnership                          Title:  Chief Executive Officer

    By: Hines Interests Limited Partnership,
        a Delaware limited partnership, sole
        member of Hines Management,
        L.L.C.

      By: Hines Holdings, Inc., a Texas
          corporation, sole member of
          Hines Interest Limited
          Partnership

          By: /s/ C. Kevin Shannahan
              --------------------------------------
                 C. Kevin Shannahan
                 Executive Vice President<PAGE>

                                                    EXHIBIT NUMBER (10)(xxix)(2)
                                                    TO 2000 FORM 10-K

                           SECOND AMENDMENT TO LEASE

             THIS SECOND AMENDMENT TO LEASE (this "Amendment"), made and entered
        into as of the 8/th/ day of September, 2000, by and between PERIMETER
                       ----
        SUMMIT PARCEL 3 LIMITED PARTNERSHIP, a Georgia limited partnership
        ("Landlord") and NORTHERN TRUST RETIREMENT CONSULTING, LLC, a Delaware
        limited liability corporation ("Tenant");

                               WITNESSETH THAT:

             WHEREAS, Landlord and Tenant entered into that certain Lease
        Agreement dated November 5, 1999, as amended by that certain First
        Amendment to Lease ("First Amendment") dated February 29, 2000
        (collectively, the "Lease") for certain premises in the building located
        at 3003 Summit Boulevard, Atlanta, Georgia 30329 (the "Building"),
        consisting of approximately 127,611 rentable square feet of space (the
        "Premises");

             WHEREAS, Tenant has elected to exercise its Expansion Option under
        Special Stipulation No. 7 to lease from Landlord certain Expansion
        Space; and

             WHEREAS, Landlord and Tenant desire to evidence such expansion of
        the Premises and to amend certain other terms and conditions of the
        Lease and evidence their agreements and other matters by means of this
        Amendment;

             NOW THEREFORE, in consideration of the mutual covenants contained
        herein, and other good and valuable consideration, the receipt, adequacy
        and sufficiency of which are hereby acknowledged, the Lease is hereby
        amended and the parties hereto do hereby agree as follows:

               1.   Tenant shall lease from Landlord an additional 12,629
                    rentable square feet of space consisting of (i) 101 rentable
                    square feet on the first (1/st/) floor of the Building; (ii)
                    132 rentable square feet on the second (2nd) floor of the
                    Building; (iii) 12,188 rentable square feet on the sixth
                    (6/th/) floor of the Building; (iv) 104 rentable square feet
                    on the seventh (7/th/) floor of the Building; and (v) 104
                    rentable square feet on the eighth (8/th/) floor of the
                    Building (collectively, the "Expansion Space"), all as shown
                    on Exhibit "A" attached hereto and by this reference made a
                    part hereof, increasing the total rentable square feet of
                    space leased pursuant to the Lease to 140,240. The leasing
                    of
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                    the portion of the Expansion Space on the seventh (7/th/)
                    and eighth (8/th/) floors includes the appurtenant right for
                    Tenant to access the leased areas through the elevator lobby
                    and corridors thereof; provided, however, if and to the
                    extent the portion of the Expansion Space located on the
                    seventh (7/th/) and eight (8/th/) floors is within another
                    tenant's premises such that such leased areas may only be
                    accessed through such other tenant's premises, then Tenant
                    agrees that Tenant's access shall be subject to such
                    reasonable rules and regulations as may be promulgated by
                    Landlord from time to time with respect to such access. The
                    leasing of the portion of the Expansion Space on the first
                    (l/st/) floor includes the appurtenant right for Tenant to
                    access the leased area from the floor below. Tenant
                    covenants and agrees that the portion of the Expansion Space
                    leased hereby located on the first (1/st/), second (2nd),
                    seventh (7/th/) and eighth (8/th/) floors may only be used
                    by Tenant for the housing of Tenant's equipment including,
                    without limitation, cabling. Landlord and Tenant acknowledge
                    and agree that the foregoing expansion is pursuant to an
                    exercise by Tenant of its Expansion Option A as set forth in
                    Expansion Schedule II of Special Stipulation No. 7 of the
                    Lease. According to the terms of such provision, all of
                    Tenant's Future Expansion Options shall be as described in
                    Expansion Schedule II and therefore, Expansion Schedule I is
                    hereby deleted from the Lease.

               2.   The Lease is hereby amended by adding the Expansion Space as
                    part of the Premises subject to and in accordance with all
                    of the terms and conditions of Special Stipulation 7 of the
                    Lease including, without limitation, (i) Base Rent at the
                    same rate per rentable square foot applicable to the
                    remainder of the Premises; (ii) a term commencing on the
                    Commencement Date (as defined therein) and expiring co-
                    terminously with the term for the remainder of the Premises,
                    and (iii) the same per rentable square foot Tenant
                    Improvement Allowance ($21.00), Construction Documents
                    Allowance ($.25), Supplemental Tenant Improvement Allowance
                    ($2.66) and Additional Allowance ($3.50) being made
                    available by Landlord to Tenant on all the same terms
                    applicable to the original Premises.

               3.   Tenant represents and warrants to Landlord that neither it
                    nor its officers or agents nor anyone acting on its behalf
                    has dealt with any real estate broker other than Hines
                    Interests Limited Partnership who represented Landlord and
                    Grubb & Ellis Company who represented Tenant in the
                    negotiating or making of this Amendment, and Tenant agrees
                    to indemnify
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                    and hold Landlord, its agents, employees, partners,
                    directors, shareholders and independent contractors harmless
                    from all liabilities, costs, demands, judgments,
                    settlements, claims, and losses, including reasonable
                    attorneys' fees and costs, incurred by Landlord in
                    conjunction with any such claim or claims of any other
                    broker or brokers claiming to have interested Tenant in the
                    Building or Premises or claiming to have caused Tenant to
                    enter into this Amendment.

               4.   Tenant hereby agrees that there are, as of the date hereof,
                    regardless of the giving of notice or the passage of time,
                    or both, no defaults or breaches on the part of Landlord or
                    Tenant under the Lease.

               5.   All capitalized terms used herein and not otherwise defined
                    herein shall have the meanings ascribed to them in the
                    Lease.

               6.   The Lease, as amended by this Amendment, represents the
                    entire agreement between the parties hereto. Landlord and
                    Tenant agree that there are no collateral or oral agreements
                    or understandings between them with respect to the Premises
                    or the Building. The Lease, as amended by this Amendment,
                    supersedes all prior negotiations, agreements, letters or
                    other statements with respect to Tenant's expansion of the
                    Premises.

               EXCEPT AS expressly amended and modified hereby, the Lease shall
          otherwise remain in full force and effect, the parties hereto hereby
          ratifying and confirming the same. To the extent of any inconsistency
          between the Lease and this Amendment, the terms of this Amendment
          shall control.

                 [Remainder of Page Intentionally Left Blank]
<PAGE>

               IN WITNESS WHEREOF, the undersigned parties have duly executed
          this Amendment as of the day and year first above written.

          TENANT:                            LANDLORD:

          NORTHERN TRUST                     PERIMETER SUMMIT PARCEL 3 LIMITED
          RETIREMENT,                        PARTNERSHIP, a Georgia limited
          CONSULTING, LLC, a                 partnership
          Delaware limited liability
          corporation                        By: 3003 Perimeter Summit Realty
                                                 Corp., a Delaware corporation,
          By: /s/ Dennis  Sain                   general partner of Perimeter
              --------------------------         Summit Parcel 3 Limited
          Name:  Dennis Sain                     Partnership
          Title: Chief Executive Officer

                                             By: /s/ Jerry Karr
                                                 ----------------------------
                                                 Name:  Jerry Karr
                                                 Title: President

                                             By:  Hines Management, L.L.C.
                                                  a Delaware limited liability
                                                  company, general partner of
                                                  Perimeter Summit Parcel 3
                                                  Limited Partnership

                                                  By:  Hines Interests Limited
                                                       Partnership, a Delaware
                                                       limited partnership, sole
                                                       member of Hines
                                                       Management, L.L.C.

                                                  By:  Hines Holdings, Inc., a
                                                       Texas corporation, sole
                                                       member of Hines
                                                       Interests Limited
                                                       Partnership

                                                  By /s/ C. Kevin Shannahan
                                                     ---------------------------
                                                         C. Kevin Shannahan
                                                         Executive Vice
                                                         President
<PAGE>

                             CONSENT OF GUARANTOR

               By its execution herein below, NORTHERN TRUST CORPORATION, the
        Guarantor under that certain Guaranty dated November 5, 1999, hereby
        consents to the amendment of the Lease and acknowledges that such
        amendment shall not operate to relieve the undersigned of its
        obligations and liabilities under such Guaranty, which obligations and
        liabilities the undersigned hereby ratifies and confirms.

                                        GUARANTOR:

                                        NORTHERN TRUST CORPORATION,
                                        a Delaware corporation

                                        By: /s/ Perry R. Pero
                                           ------------------------
                                           Name:  Perry R. Pero
                                           Title: Vice Chairman
<PAGE>

                               CONSENT OF LENDER

          By its execution herein below, WACHOVIA BANK, N.A., the lender under
          that certain deed to secure debt, assignment and security agreement
          and party to that certain Subordination, NonDisturbance and Attornment
          Agreement dated November 5, 1999 (the "SNDA") by and among Landlord,
          Tenant and the undersigned, hereby consents to the amendment of the
          Lease for purposes of Section 2 of the SNDA.

                                    LENDER:

                                    WACHOVIA BANK, N.A.

                                   By: /s/ William N. Nelson
                                      --------------------
                                   Name:   William N. Nelson
                                   Title:  Senior Vice President
<PAGE>

                                  Exhibit "A"

                                Expansion Space

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