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                                                                   Exhibit 10.12

                             XPEDIOR INCORPORATED
                           1999 STOCK INCENTIVE PLAN

                      Nonstatutory Stock Option Agreement

     THIS AGREEMENT is made as of the 13/th/ day of March 2000, between XPEDIOR
INCORPORATED, a Delaware corporation (the "Company"), and Caesar J. Belbel
("Employee") in order to carry out the purposes of the XPEDIOR INCORPORATED 1999
STOCK INCENTIVE PLAN  (the "Plan"), by affording Employee the opportunity to
purchase shares of Common Stock, $.01 par value per share, of the Company (the
"Common Stock"), and in consideration of the mutual agreements and other matters
set forth herein and in the Plan, the Company and Employee hereby agree as
follows:

                                       I.
                                  Definitions
                                  -----------

     1.1  Definitions.  Wherever used in this Agreement, the following words and
phrases shall have the meanings ascribed below, unless the context clearly
indicates to the contrary, and all other capitalized terms used in this
Agreement, which are not defined below or elsewhere in this Agreement, shall
have the meanings set forth in the Plan:

          1.1.1  "Act" shall mean the Securities Act of 1933, as amended.

          1.1.2  "Agreement" shall mean this nonstatutory stock option agreement
     between Employee and the Company.

          1.1.3  "Cause" shall mean "cause" as defined in Employee's employment
     agreement with the Company or any Affiliate and, in the absence of such an
     employment agreement or such a definition, "Cause" shall mean a
     determination by the Committee that Employee (i) has engaged in negligence
     or willful misconduct in the performance of his employment duties, (ii) has
     substantially failed to meet any material expectations associated with
     Employee's employment position, because of substandard performance by
     Employee of his employment duties, (iii) has been convicted of a
     misdemeanor involving moral turpitude or of any felony, (iv) has willfully
     refused without proper legal reason to perform his employment duties and
     responsibilities, (v) has materially breached any corporate policy or code
     of conduct established by the Company, (vi) has breached any provision of
     any agreement with the Company or any Affiliate, or (vii) has engaged in
     dishonest or fraudulent conduct with respect to the business, reputation,
     or affairs of the Company or any Affiliate.

          1.1.4  "Change in Control" shall mean the occurrence of any one of the
     following:  (i) the Company shall not be the surviving entity in any merger
     or consolidation (or survives only as a wholly-owned subsidiary of another
     entity); (ii) the Company sells, leases, or exchanges, or agrees to sell,
     lease, or exchange, all or substantially all its assets to any person or
     entity, or any entity controlled by, or under common control with, the
     Company as of the date of this Agreement; (iii) any person,
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     entity, or "group" as contemplated by Section 13(d)(3) of the Securities
     Exchange Act of 1934, as amended (the "Exchange Act"), other than Metamor
     Worldwide, Inc., a Delaware corporation ("Metamor") PSINet, becomes the
     beneficial owner (within the meaning of Rule 13d-3 under the Exchange Act)
     of more than 50% of the outstanding shares of voting capital stock of the
     Company; or (iv) as a result of, or in connection with, any cash tender
     offer or exchange offer, merger, consolidation, share exchange, or other
     business combination, sale of assets, or a contested election of the board
     of directors of the Company, or any combination of the foregoing
     transactions (each, a "Transaction"), (A) the persons who were directors of
     the Company prior to such Transaction shall cease to constitute a majority
     of the board of directors of the Company after the Transaction or (B) less
     than seventy percent (70%) of the outstanding voting securities of the
     surviving person or entity is owned or controlled by the stockholders of
     the Company immediately prior to the Transaction, excluding any stockholder
     who is an interested party to the Transaction.

          1.1.5  "Date of Grant" shall mean March 13, 2000.

          1.1.6  "Good Reason" shall mean the occurrence of any of the following
     events without Employee's written consent:  (i) a substantial and adverse
     change in Employee's duties, control, authority, status, or position with
     the Company, or the assignment to Employee of any duties or
     responsibilities that are materially inconsistent with such status or
     position, or a material reduction in the duties and responsibilities
     previously exercised by Employee associated with such position, or a loss
     of title, loss of office, relocation of office outside of the Greater
     Boston Area, loss of significant authority, power, or control associated
     with such position, or any removal of Employee from, or any failure to
     reappoint or reelect Employee to, such position, except in connection with
     the termination of Employee's employment with the Company for Cause or
     total disability or as a result of death; (ii) any reduction in Employee's
     base salary from the Company unless such reduction shall also apply to
     similarly situated executives of the Company and does not exceed ten
     percent (10%) per year; or (iii) any material breach by the Company of
     Employee's employment agreement with the Company.

          1.1.7  "Merger" shall mean the merger by and among Metamor, PSINet,
     and PSINet SHELF IV Inc.

          1.1.8  "Option" shall mean the right and option to purchase shares of
     Stock on the terms set forth in this Agreement and the Plan.

          1.1.9  "Qualified IPO Date" shall mean December 16, 1999.

          1.1.10  "Restricted Period" shall mean the period beginning on the
     date hereof and ending on the earlier of (i) the occurrence of the Spin-
     Off, (ii) the closing of the Merger, or (iii) the second anniversary of the
     Qualified IPO Date.

          1.1.11  "Spin-Off" shall mean the date of completion of a spin-off of
     all of the Stock of the Company held by Metamor to its stockholders through
     dividend, share exchange, or similar transaction.

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          1.1.12  "Stock" shall mean shares of Common Stock.

          1.1.13  "Vested Interest" shall mean the nonforfeitable percentage
     determined in accordance with Section IV thereof.

                                      II.
                       Grant of Option and Purchase Price
                       ----------------------------------

     2.1  Grant of Option.  The Company hereby irrevocably grants to Employee
the Option to purchase all or any part of an aggregate of 70,000 shares of
Common Stock, on the terms and conditions set forth herein and in the Plan,
which Plan is incorporated herein by reference as a part of this Agreement.
This Option shall not be treated as an incentive stock option within the meaning
of section 422(b) of the Code.

     2.2  Purchase Price.  The purchase price of the Stock purchased pursuant to
the exercise of this Option shall be $16.06 per share which has been determined
to be the Fair Market Value of the Stock at the date of grant of this Option.

                                      III.
                               Exercise of Option
                               ------------------

     3.1  Exercise of Option.  Subject to the earlier expiration of this Option
as herein provided, this Option may be exercised, by written notice to the
Company at its principal executive office addressed to the attention of its
Chief Executive Officer, at any time and from time to time after the date of
grant hereof, but, except as otherwise provided in this Section III, this Option
(i) shall be exercisable only for the shares offered by this Option in which
Employee has acquired a Vested Interest in accordance with Section IV, and (ii)
shall not be exercisable in whole or in part prior to the end of the Restricted
Period.

     3.2  Termination of Employment.  This Option may be exercised only while
Employee remains an employee of the Company and will terminate and cease to be
exercisable upon Employee's termination of employment with the Company, except
as follows:

          3.2.1  If Employee's employment with the Company terminates by reason
     of disability (within the meaning of section 22(e)(3) of the Code), this
     Option may be exercised by Employee (or Employee's estate or the person who
     acquires this Option by will or the laws of descent and distribution or
     otherwise by reason of the death of Employee) at any time during the period
     of one year following the later of (i) such termination and (ii) the end of
     the Restricted Period, but only as to the number of shares in which
     Employee had a Vested Interest as of the date Employee's employment so
     terminates.

          3.2.2  If Employee dies while in the employ of the Company, Employee's
     estate, or the person who acquires this Option by will or the laws of
     descent and distribution or otherwise by reason of the death of Employee,
     may exercise this Option at any time during the period of one year
     following the later of (i) the date of Employee's death and

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     (ii) the end of the Restricted Period, but only as to the number of shares
     in which Employee had a Vested Interest as of the date of Employee's death.

          3.2.3  If Employee's employment with the Company terminates for any
     reason other than as described in Subparagraph 3.2.1 or 3.2.2 above, unless
     Employee voluntarily terminates such employment or such employment is
     terminated for Cause, this Option may be exercised (A) by Employee at any
     time during the period of three months following the later of (i) such
     termination and (ii) the end of the Restricted Period, or (B) if Employee
     dies during such three-month period or during the Restricted Period, by
     Employee's estate (or the person who acquires this Option by will or the
     laws of descent and distribution or otherwise by reason of the death of
     Employee) during a period of one year following the later of (i) Employee's
     death and (ii) the end of the Restricted Period, but in each case only as
     to the number of shares in which Employee had a Vested Interest as of the
     date Employee's employment so terminates. The Committee may, in its sole
     discretion, advise Employee in writing, prior to a voluntary termination of
     Employee's employment, that such termination will be treated for purposes
     of this Section as an involuntary termination for a reason other than
     Cause.

     3.3  Ten-Year Term.  This Option shall not be exercisable in any event
after the expiration of ten years from the date of grant hereof.

     3.4  Method of Payment.  The purchase price of shares as to which this
Option is exercised shall be paid in full at the time of exercise (i) in cash
(including check, bank draft, or money order payable to the order of the
Company), (ii) by delivering to the Company shares of Stock having a Fair Market
Value equal to the purchase price, or (iii) any combination of cash or Stock.
No fraction of a share of Stock shall be issued by the Company upon exercise of
an Option or accepted by the Company in payment of the purchase price thereof;
rather, Employee shall provide a cash payment for such amount as is necessary to
effect the issuance and acceptance of only whole shares of Stock.

     3.5  Issuance of Certificate.  Unless and until a certificate or
certificates representing such shares shall have been issued by the Company to
Employee, Employee (or any other person permitted to exercise this Option
pursuant to the terms of the Plan and this Agreement) shall not be or have any
of the rights or privileges of a stockholder of the Company with respect to
shares acquirable upon an exercise of this Option.

     3.6  Cashless Exercise.  Employee (or the person permitted to exercise this
Option in the event of Employee's death or disability) may direct, in a properly
executed written notice, an immediate market sale or margin loan respecting all
or any part of the shares of Stock to which he is entitled upon exercise of this
Option pursuant to an extension of credit by the Company, on an interest-free
basis, to Employee of the purchase price.  In such event, the Company shall
deliver the specified number of shares of Stock directly to the broker specified
in the notice and shall accept payment of the purchase price in cash or by check
from such broker on behalf of Employee and shall take all action necessary to
comply with the provisions of the applicable regulations of the Securities
Exchange Act of 1934 and with such additional rules and regulations as may be
applicable.  Notwithstanding the foregoing, the Company shall not be required to
comply with, and may unilaterally terminate, all or any of the provisions of
this Section 3.6 if, as a result of a change in the accounting rules and
regulations applicable to the

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Company, or the interpretation thereof, compliance with such provisions will
result in the imposition of adverse financial reporting requirements on the
Company.

                                      IV.
                                    Vesting
                                    -------

     4.1  Vesting of Shares.  Subject to the forfeiture provisions of Section
4.3 hereof, Employee shall acquire a Vested Interest in the shares subject to
this Option in accordance with Section 4.2 or 4.3 below, as applicable.
Notwithstanding Employee's acquisition of a Vested Interest pursuant to this
Section IV, no Option or portion thereof shall be exercisable by Employee prior
to the time provided in Section III or in any manner except as provided in
Section III.

     4.2  36-Month Vesting Schedule.  As long as Employee is continuously
employed by the Company, Employee shall acquire a Vested Interest in 1,944
shares of Stock subject to this Option per month over the first thirty five (35)
month period following the Date of Grant, and a Vested Interest in 1,960 shares
of Stock subject to this Option following the thirty sixth (36th) month
following the Date of Grant. Upon termination of Employee's employment with the
Company for any reason, including, but not limited to, death and disability,
Employee shall cease to acquire a Vested Interest in the shares subject to this
Option.

     4.3  Accelerated Vesting Upon Termination Following Change in Control.  If,
within one year following the occurrence of a Change in Control, either (i)
Employee's employment with the Company is involuntarily terminated other than
for Cause or (ii) Employee terminates employment with the Company for Good
Reason, Employee shall acquire a Vested Interest in the lesser of (A) all shares
subject to this Option in which Employee has not yet acquired a Vested Interest;
or (B) 23,328 shares subject to this Option.

     4.4  Forfeiture of Vested Interest.  Employee shall forfeit his Vested
Interest in his Option and any and all shares acquired pursuant to the exercise
of such Option if (i) Employee's employment with the Company or an Affiliate is
terminated for Cause or (ii) in the opinion of the Committee Employee has
engaged in conduct that would amount to "Cause" at any time within the period
beginning on the date of Employee's termination of employment (for any reason)
with the Company or an Affiliate and ending six months after the later of (i)
the end of the Restricted Period or (ii) the date that is three months following
such termination of employment.  In the event of such a forfeiture, Employee
shall surrender to the Company the unexercised portion of his Option and all
shares acquired pursuant to the exercise of such Option.  The forfeiture
provisions provided in this Section 4.4 shall be in addition to the forfeiture
and rescission provisions applicable to Awards under Section 5.2 of the Plan.

                                       V.
                                Status of Stock
                                ---------------

     5.1  Status of Stock.  With respect to the status of the Stock, at the time
of execution of this Agreement Employee understands and agrees to all of the
following:

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          5.1.1  The Company has registered for issuance under the Securities
     Act of 1933, as amended (the "Act") the shares of Stock acquirable upon
     exercise of this Option, and intends to keep such registration effective
     throughout the period this Option is exercisable. In the absence of such
     effective registration or an available exemption from registration under
     the Act, issuance of shares of Stock acquirable upon exercise of this
     Option will be delayed until registration of such shares is effective or an
     exemption from registration under the Act is available. The Company intends
     to use its best efforts to ensure that no such delay will occur. In the
     event exemption from registration under the Act is available upon an
     exercise of this Option, Employee (or the person permitted to exercise this
     Option in the event of Employee's death or incapacity), if requested by the
     Company to do so, will execute and deliver to the Company in writing an
     agreement containing such provisions as the Company may require to assure
     compliance with applicable securities laws.

          5.1.2  Employee agrees that the shares of Stock which Employee may
     acquire by exercising this Option will not be sold or otherwise disposed of
     in any manner that would constitute a violation of any applicable
     securities laws, whether federal or state.

          5.1.3  Employee agrees that (i) the certificates representing the
     shares of Stock purchased under this Option may bear such legend or legends
     as the Committee deems appropriate in order to assure compliance with
     applicable securities laws, (ii) the Company may refuse to register the
     transfer of the shares of Stock purchased under this Option on the stock
     transfer records of the Company if such proposed transfer would in the
     opinion of counsel satisfactory to the Company constitute a violation of
     any applicable securities law and (iii) the Company may give related
     instructions to its transfer agent, if any, to stop registration of the
     transfer of the shares of Stock purchased under this Option.

                                      VI.
                                 Miscellaneous
                                 -------------

     6.1  Employment Relationship.  For purposes of this Agreement, Employee
shall be considered to be in the employment of the Company as long as Employee
remains an employee of either the Company, a parent or subsidiary corporation
(as defined in section 424 of the Code) of the Company, or a corporation or a
parent or subsidiary of such corporation assuming or substituting a new option
for this Option.  Any question as to whether and when there has been a
termination of such employment, and the cause of such termination, shall be
determined by the Committee, and its determination shall be final.

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     6.2  Notices.  For purposes of this Agreement, notices and all other
communications provided for herein shall be in writing and shall be deemed to
have been duly given when personally delivered or when mailed by United States
registered or certified mail, return receipt requested, postage prepaid,
addressed as follows:

     If to the Company to:          Xpedior Incorporated
                                    One North Franklin Street
                                    Suite 1500
                                    Chicago, Illinois 60606
                                    Attention: J. Brian Farrar
                                               Executive Vice President
                                                 and Chief Operating Officer


     If to Employee to:             Caesar J. Belbel
                                    21 Penniman Road
                                    Brookline, Massachusetts 02445-4127

or to such other address as either party may furnish to the other in writing in
accordance herewith, except that notices or changes of address shall be
effective only upon receipt.

     6.3  Withholding of Tax.  To the extent that the exercise of this Option or
the disposition of shares of Stock acquired by exercise of this Option results
in compensation income to Employee for federal or state income tax purposes,
Employee shall deliver to the Company at the time of such exercise or
disposition such amount of money or shares of Stock as the Company may require
to meet its obligation under applicable tax laws or regulations, and, if
Employee fails to do so, the Company is authorized to withhold from any cash or
Stock remuneration then or thereafter payable to Employee any tax required to be
withheld by reason of such resulting compensation income.  Upon an exercise of
this Option, the Company is further authorized in its discretion to satisfy any
such withholding requirement out of any cash or shares of Stock distributable to
Employee upon such exercise.

     6.4  Binding Effect.  This Agreement shall be binding upon and inure to the
benefit of any successors to the Company and all persons lawfully claiming under
Employee.

     6.5  Governing Law.  This Agreement shall be governed by, and construed in
accordance with, the laws of the Commonwealth of Massachusetts.

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     IN WITNESS WHEREOF, the Company has caused this Agreement to be duly
executed by its officer thereunto duly authorized, and Employee has executed
this Agreement, all as of the day and year first above written.


                                 XPEDIOR INCORPORATED



                                 By:  /s/ David N. Campbell
                                     ------------------------------------------
                                 Name:    David N. Campbell
                                 Title:   President and Chief Executive Officer



                                 /s/ Caesar J. Belbel
                                 ----------------------------------------------
                                     CAESAR J. BELBEL

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