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                                                                    Exhibit 10.6
                       Cabot Industrial Properties, L.P.
                          Two Center Plaza, Suite 200
                             Boston, MA 02108-1906


                               September 10, 1998

Ferdinand Colloredo-Mansfeld:
46 Winthrop Street
South Hamilton, MA 01982


Dear Mr. Colloredo-Mansfeld:

     This letter reflects our agreement relative to your appointment as Chairman
of Cabot Industrial Trust (the "Trust") and your employment by Cabot Industrial
Properties, L.P. (the "Partnership").

     The Partnership agrees to employ you in such capacity for a three-year term
(the "Term"), beginning February 4, 1998 (the "Effective Date").  After the
first anniversary of the Effective Date and on each successive anniversary
thereof, the Term shall be automatically extended for an additional twelve-month
period, unless you or the Partnership provides written notice of non-renewal to
the other at least 120 days before any such anniversary.  During the Term, while
you are employed by the Partnership, you agree that you shall devote
substantially all of your business time, energies and talents to serving as
Chairman of the Trust, you shall perform your duties faithfully and efficiently
subject to the directions of the Board of Trustees of the Trust and you will not
engage, directly or indirectly, in any activities that compete with those of the
Trust or the Partnership.

     During the Term while you are employed by the Partnership, you will be paid
base compensation in the amount of $265,000 per year and you will be eligible
for a cash bonus in such amount as may be determined by the Board of Trustees of
the Trust or the Compensation Committee thereof, in its sole discretion.  The
amount of your base compensation and your bonus will be reviewed by the Board
each year during the Term.  You also will be granted such options under the
Cabot Industrial Trust Long Term Incentive Plan (the "Plan") as the committee of
the Plan determines.

     If, during the Term, after a Change in Control (as described in the Plan),
(i) the Trust or the Partnership or the successor of either  (A) terminates your
employment without Cause (as defined below) or does not extend the Term or (B)
constructively terminates your employment by substantially adversely altering
either your status or responsibilities or your annual base compensation and
bonus from those in effect immediately prior to the Change in Control or by
moving the location of your office more than 50 miles from its then current
location, or (ii) if you terminate your employment on or before the first
anniversary of the Change in Control, you
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will be entitled to a lump sum payment as soon as practicable after the date of
such termination, subject to payroll tax withholding as required by law, in an
amount equal to three times the sum of the rate of your annual base compensation
as in effect on such date (or as in effect on the date of the Change in Control,
if higher) plus the amount of your bonus for the year prior to the year in which
your employment terminates; provided, that if termination occurs prior to the
time that a bonus has first been awarded to you hereunder the amount of the
bonus shall be deemed to be the amount of your target incentive bonus as
established by the Board of Trustees or the Compensation Committee thereof or,
if such target bonus has not then been established, 30% of the rate of your
annual base compensation as in effect on such date. In the event it is
determined that any payment or benefit (or combination thereof), including
acceleration of any share options, by the Trust to you or for your benefit would
be subject to the excise tax imposed by section 4999 of the Internal Revenue
Code, the Trust or the Partnership shall pay you a tax gross-up payment in
accordance with Exhibit A, which is attached to and forms a part of this
agreement. For purposes of this agreement, "Cause" shall mean your willful
engaging in conduct which is demonstrably monetarily injurious to the Trust or
the Partnership or your engaging in egregious misconduct involving serious moral
turpitude.

     This letter amends and restates in full our prior Agreement, dated February
4, 1998.  If this letter satisfactorily reflects our agreement, as amended,
please sign and return the attached copy to my attention.  Thank you for your
efforts on behalf of the Trust and the Partnership.

                                    /s/ Robert E. Patterson
                                    _________________________
                                      Robert E. Patterson,
                                      President

Accepted as of this 4th day of
February, 1998.
/s/ Ferdinand Colloredo-Mansfeld
________________________________
Ferdinand Colloredo-Mansfeld
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                                   Exhibit A
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                              Tax Gross-Up Payment
                              --------------------

1.   Gross-Up Payment.  In the event that it is determined that any payments,
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     benefits or distributions (or any combination thereof) to or for the
     benefit of Executive (whether paid or payable or distributed or
     distributable pursuant to the terms of the attached letter agreement, or
     otherwise) by the Trust or any of its affiliates (including the
     Partnership) or by one or more trusts established by the Trust or any of
     its affiliates for the benefit of their employees, are subject to the
     excise tax imposed by section 4999 of the Internal Revenue Code of 1986, as
     amended (the "Code"),  which payments are collectively referred to as
     "Parachute Payments", the Trust or the Partnership shall pay to or for the
     benefit of Executive a payment (a "Gross-Up Payment") equal to the sum of
     the following amounts:

     a.   the amount of the excise tax attributable to the Parachute Payments
          (referred to as the "Excise Tax") and the amount of any additional
          excise tax under section 4999 of the Code imposed with respect to
          additional payments, if any, made pursuant to this paragraph 1;

     b.   any interest or penalties incurred by Executive with respect to the
          Excise Tax and other payments, if any, made pursuant to this paragraph
          1; and

     c.   any taxes, including income taxes, incurred by Executive on the Excise
          Tax and other payments, if any, made pursuant to this paragraph 1.

2.   Determination and Payment of Gross-Up Payment.  Subject to the provisions
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     of paragraph 3 below, all determinations required to be made under this
     Exhibit A, including whether and when a Gross-Up Payment is required and
     the amount of such Gross-Up Payment and the assumptions to be utilized in
     arriving at such determination, shall be made by a nationally recognized
     certified public accounting firm as may be designated by the Trust or the
     Partnership (the "Accounting Firm") which shall provide detailed supporting
     calculations to the Trust, the Partnership and Executive within fifteen
     (15) business days of the effective time of a Change in Control or such
     earlier time as is requested by the Trust or the Partnership.  All fees and
     expenses of the Accounting Firm shall be borne solely by the Trust or the
     Partnership.  Any Gross-Up Payment, as determined pursuant to paragraph 1,
     shall be paid by the Trust or the Partnership to Executive within five (5)
     days after the receipt of the Accounting Firm's determination. If the
     Accounting Firm determines that no Excise Tax is payable by Executive, it
     shall so indicate to Executive in writing.  Any determination by the
     Accounting Firm shall be binding upon the Trust, the Partnership and
     Executive.  As a result of the uncertainty in the application of section
     4999 of the Code at the time of the initial determination by the Accounting
     Firm hereunder, it is possible that a Gross-Up Payment which will not have
     been made by the Trust or the Partnership should have been made
     ("Underpayment"),
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     consistent with the calculations required to be made hereunder. In the
     event that the Trust or the Partnership exhausts its remedies pursuant to
     paragraph 3 and Executive thereafter is required to make a payment of any
     Excise Tax, the Accounting Firm shall determine the amount of the
     Underpayment that has occurred and any such Underpayment shall be promptly
     paid by the Trust or the Partnership to or for the benefit of Executive.

3.   Claims by IRS.  Executive shall notify the Trust and the Partnership in
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     writing of any claim by the Internal Revenue Service that, if successful,
     would require the payment by the Trust or the Partnership of the Gross-Up
     Payment.  Such notification shall be given as soon as practicable but no
     later than ten (10) business days after Executive is informed in writing of
     such claim and shall apprise the Trust and the Partnership of the nature of
     such claim and the date on which such claim is requested to be paid.
     Executive shall not pay such claim prior to the expiration of the thirty
     (30) day period following the date on which it gives such notice to the
     Trust and the Partnership (or such shorter period ending on the date that
     any payment of taxes with respect to such claim is due).  If the Trust or
     the Partnership notifies Executive in writing prior to the expiration of
     such period that it desires to contest such claim, Executive shall:

     a.   give the Trust and the Partnership any information requested by either
          relating to such claim;

     b.   take such action in connection with contesting such claim as the Trust
          or the Partnership shall reasonably request in writing from time to
          time, including, without limitation, accepting legal representation
          with respect to such claim by an attorney reasonably selected by the
          Trust or the Partnership;

     c.   cooperate with the Trust and the Partnership in good faith in order to
          effectively contest such claim; and

     d.   permit the Trust and the Partnership to participate in any proceedings
          relating to such claim;

     provided, however, that the Trust or the Partnership shall bear and pay
     directly all costs and expenses (including additional interest and
     penalties) incurred in connection with such contest and shall indemnify and
     hold Executive harmless, on an after-tax basis, for any Excise Tax or
     income tax (including interest and penalties with respect thereto) imposed
     as a result of such representation and payment of costs and expenses.
     Without limitation on the foregoing provisions of this paragraph 3, the
     Trust or the Partnership shall control all proceedings taken in connection
     with such contest and, at its sole option, may pursue or forego any and all
     administrative appeals, proceedings, hearings and conferences with the
     taxing authority in respect of such claim and may, at its sole option,
     either direct Executive to pay the tax claimed and sue for a refund or
     contest the claim in any permissible manner, and Executive agrees to
     prosecute such contest to a

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     determination before any administrative tribunal, in a court of initial
     jurisdiction and in one or more appellate courts, as the Trust or the
     Partnership shall determine; provided, however, that if the Trust or the
     Partnership directs Executive to pay such claim and sue for a refund, the
     Trust or the Partnership shall advance the amount of such payment to
     Executive, on an interest-free basis, and shall indemnify and hold
     Executive harmless, on an after-tax basis, from any Excise Tax or income
     tax (including interest or penalties with respect thereto) imposed with
     respect to such advance or with respect to any imputed income with respect
     to such advance; and provided, further, that if Executive is required to
     extend the statute of limitations to enable the Trust or the Partnership to
     contest such claim, Executive may limit this extension solely to such
     contested amount. The control of the contest by the Trust or the
     Partnership shall be limited to issues with respect to which a Gross-Up
     Payment would be payable hereunder and Executive shall be entitled to
     settle or contest, as the case may be, any other issue raised by the
     Internal Revenue Service or any other taxing authority.

4.   Refunds.  If, after the receipt by Executive of an amount advanced by the
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     Trust or the Partnership pursuant to paragraph 3, Executive becomes
     entitled to receive any refund with respect to such claim, Executive shall
     (subject to the Trust's or the Partnership's complying with the
     requirements of paragraph 3) promptly pay to the Trust or the Partnership
     the amount of such refund (together with any interest paid or credited
     thereon after taxes applicable thereto).  If, after the receipt by
     Executive of an amount advanced by the Trust or the Partnership pursuant to
     paragraph 3, a determination is made that Executive shall not be entitled
     to any refund with respect to such claim and the Trust or the Partnership
     does not notify Executive in writing of its intent to contest such denial
     of refund prior to the expiration of thirty (30) days after such
     determination, then such advance shall be forgiven and shall not be
     required to be repaid and the amount of such advance shall offset, to the
     extent thereof, the amount of Gross-Up Payment required to be paid.

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