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                                                                    Exhibit 10.6

                       FORM OF TAX ALLOCATION AGREEMENT
                       --------------------------------

     This Tax Allocation Agreement (this "Agreement") is entered into as of
______________, 2000 by and between Arthur D. Little, Inc., a Massachusetts
corporation, and c-quential, Inc., a Delaware corporation.

     WHEREAS, the execution and delivery of this Agreement is a condition to the
transactions contemplated by the Reorganization Agreement dated as of
_______________, 2000 by and among Arthur D. Little, Inc., c-quential, Inc. and
other parties thereto (the "Reorganization Agreement");

     NOW, THEREFORE, in consideration of the mutual promises and agreements set
forth herein, and other valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto agree as follows:

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

     Section 1.1  Defined Terms.  For purposes of this Agreement, the following
                  -------------
terms shall have the following meanings.

     "Affiliated Group" means an affiliated group within the meaning of Section
1504(a) of the Code.

     "Ancillary Agreement" shall have the meaning given to such term in the
Reorganization Agreement, excluding this Agreement.

     "ADL Affiliated Group" means Parent and all other corporations that may now
or from time to time hereafter constitute an Affiliated Group with Parent as the
Common Parent.

     "Code" means the Internal Revenue Code of 1986, as amended.

     "Combined Return" means any Return (other than a Consolidated Return) that
is filed on a consolidated, combined or unitary basis (including any state,
local, or foreign Return filed on such basis) that includes at least one Parent
Subsidiary and one Sub Subsidiary.

     "Combined Tax" means any Tax reported on a Combined Return.

     "Combined Utilized Tax Benefit" means, for any period reported on a
Combined Return, the reduction (if any) in Combined Taxes resulting from the use
by the group of entities included in such Combined Return of any credits,
deductions, losses or other items attributable to the Sub Subsidiaries that
could not be used to reduce the Hypothetical Combined Tax or increase the
Hypothetical Combined Refund for such period or any prior period reported on a
Combined Return.

     "Common Parent" means the common parent, within the meaning of Section
1504(a) of the Code, of an Affiliated Group.
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     "Consolidated Return" means the Federal Income Tax Return of the ADL
Affiliated Group for any Consolidated Return Year.

     "Consolidated Return Year" means any taxable year (i) during any part of
which Sub is a member of the ADL Affiliated Group, and (ii) with respect to
which the ADL Affiliated Group files a consolidated Federal Income Tax Return
under Section 1501 of the Code.

     "Consolidated Tax" means any Tax reported on a Consolidated Return.

     "Effective Date" shall have the meaning given to such term in the
Reorganization Agreement.

     "Estimated Payment Date" means any date in a Consolidated Return Year upon
which the ADL Affiliated Group is required to make a payment of estimated
Federal Income Tax.

     "Federal Income Tax" means any Tax imposed by Subtitle A of the Code.

     "Federal Income Tax Return" means a Return filed with respect to Federal
Income Taxes.

     "Federal Utilized Tax Benefit" means, for any Consolidated Return Year, the
reduction (if any) in Consolidated Taxes resulting from the use by the ADL
Affiliated Group of any credits, deductions, losses or other items attributable
to the Sub Group that could not be used to reduce the Hypothetical Federal Tax
or increase the Hypothetical Federal Refund for such Consolidated Return Year or
any prior Consolidated Return Year.

     "Hypothetical Combined Tax" and "Hypothetical Combined Refund" are defined
in Section 5.

     "Hypothetical Federal Tax" and "Hypothetical Federal Refund" are defined in
Section 4.

     "Independent Director" with respect to Sub, shall mean a member of the Sub
Board of Directors who is not an employee or officer of Sub or an officer,
employee or director of Parent or a member of the Parent Group, and with respect
to Parent, shall mean a member of the Parent Board of Directors who is not an
employee or officer of Parent or a member of the Parent Group.

     "Parent" means Arthur D. Little, Inc., a Massachusetts corporation, or any
successor thereto.

     "Parent Group" means the ADL Affiliated Group excluding the Sub Group.

     "Parent Subsidiary" means Parent or any entity in which Parent holds a
direct or indirect interest, excluding all Sub Subsidiaries.

     "Reorganization Agreement" is defined in the recitals to this Agreement.

     "Reorganization Tax" means any Tax imposed upon any Parent Subsidiary or
Sub Subsidiary with respect to the Reorganization Transaction, including but not
limited to any transfer Tax and any Tax imposed on realized gain.

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     "Reorganization Tax Benefit" means the excess of (i) the Total Sub Taxes
that would be incurred if the Reorganization Transaction were treated as giving
rise to no Reorganization Tax over (ii) the Total Sub Taxes actually incurred.
Whenever the Reorganization Tax Benefit is calculated, each of the amounts
referred to in clauses (i) and (ii) of the preceding sentence shall be such
amounts as of the date of the calculation.

     "Reorganization Transaction" means all of the transactions contemplated in
the Reorganization Agreement and Ancillary Agreements considered collectively,
excluding transactions contemplated in the Corporate Services Agreement, the
Registration Rights Agreement or the Use and Occupancy Agreement.

     "Return" means any Tax return, statement, report, form or election
(including, without limitation, estimated Tax returns and reports, extension
requests and forms, and information returns and reports) required to be filed
with any Taxing Authority, in each case as amended.

     "Return Due Date" means, with respect to any Return, the earlier of (i) the
due date (including extensions) of such Return, or (ii) the date such Return is
filed.

     "Spin-Off" means a distribution of stock of Sub that is intended to qualify
as a transaction described in Section 355 of the Code.

     "Spin-Off Tax" means any Tax incurred by the Parent Group or the Sub Group
(i) as a result of a Spin-Off failing to qualify as a transaction described in
Section 355 of the Code, or (ii) through the application of Section 355(d) or
(e) of the Code to a Spin-Off.

     "Sub" means c-quential, Inc., a Delaware corporation, or any successor
thereto.

     "Sub Group" means the group of corporations that would constitute a
separate Affiliated Group with Sub as the Common Parent if Sub were not a member
of the ADL Affiliated Group.

     "Sub Subsidiary" means Sub or any entity in which Sub holds a direct or
indirect interest.

     "Tax" means any tax imposed by the Code, and any net income, capital gains,
alternative or add-on minimum, gross income, gross receipts, sales, use, ad
valorem, value added, transfer, franchise, profits, license, withholding (as
payor or recipient), payroll, employment, excise, severance, stamp, capital
stock, occupation, property, real property gains, environmental, windfall,
premium, custom, duty or other tax, recording fee, governmental fee or other
like assessment or charge of any kind whatsoever imposed by any domestic or
foreign jurisdiction, together with any related interest, penalties, additions
to tax and related costs and expenses (including but not limited to legal and
accounting fees).

     "Tax Adjustment" means any adjustment (whether positive or negative)
required by a Taxing Authority, or appearing in an amended Return, to any Tax
liability or item reflected (or which should have been reflected) in any Return.

     "Tax Advisor" means an attorney, law firm, accountant, accounting firm or
other person designated by a party as its tax advisor.

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     "Tax Dispute" means any dispute, controversy or claim between any Parent
Subsidiary and any Sub Subsidiary arising out of or relating to this Agreement,
including without limitation the breach, interpretation or validity of any term
or condition hereof, or the withholding by Sub or Parent (whether reasonably or
unreasonably) of any approval required hereunder other than a consent described
in Section 6.1.

     "Taxing Authority" means any governmental authority or any subdivision,
agency, commission or authority thereof, or any quasi-governmental or private
body having jurisdiction over the assessment, determination, or imposition of
any Tax.

     "Tax Proceeding" means any Tax audit, dispute or proceeding (whether
administrative or judicial).

     "Total Sub Taxes" means the sum of (i) Taxes paid by Sub Subsidiaries, (ii)
Hypothetical Federal Taxes and (iii) Hypothetical Combined Taxes, less the sum
of (x) Tax refunds received by Sub Subsidiaries, (y) Hypothetical Federal
Refunds and (z) Hypothetical Combined Refunds.  Whenever Total Sub Taxes are
calculated, each of the amounts referred to in clauses (i), (ii), (iii), (x),
(y) and (z) of the preceding sentence shall be the total of all such amounts
(with Tax Adjustments taken into account) for all periods beginning on or after
the Effective Date (or, with respect to any period beginning before and ending
after the Effective Date, the portion of such period beginning on the day after
the Effective Date) and ending on or before the date of the calculation.  Total
Sub Taxes may be either positive or negative.

SECTION 2.  TAX RETURNS, PAYMENTS AND PROCEEDINGS.
            -------------------------------------

     Section 2.1  Consolidated Returns.
                  --------------------

          (a) Parent shall be responsible for the preparation and filing of all
Consolidated Returns; provided, however, that Sub shall have the right to
review, at least 10 days prior to the Return Due Date of any Consolidated
Return, a draft of the portion of such Return that reflects the operations and
tax items of the Sub Group.

          (b) Parent shall be responsible for the payment of all Federal Income
Taxes attributable to Consolidated Return Years, and shall be entitled to all
Federal Income Tax refunds attributable to Consolidated Return Years.

     Section 2.2  Combined Returns.
                  ----------------

          (a) Parent shall be responsible for the preparation and filing of all
Combined Returns; provided, however, that Sub shall have the right to review, at
least 10 days prior to the Return Due Date of any Combined Return, a draft of
the portion of such Return that reflects the operations and tax items of the Sub
Subsidiaries included in such Return.

          (b)  Parent shall be responsible for the payment of all Taxes
attributable to periods and items reflected (or which should have been
reflected) in any Combined Return, and shall be entitled to all Tax refunds
attributable to periods and items reflected (or which should have been
reflected) in any Combined Return.

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     Section 2.3  Tax Proceedings Respecting Consolidated and Combined Returns.
                  ------------------------------------------------------------
Tax Proceedings respecting any Consolidated Return or Combined Return shall be
controlled by Parent.

     Section 2.4  Other Party's Tax Objectives Taken Into Account.  In the
                  -----------------------------------------------
preparation of all Returns and in the conduct of all Tax Proceedings--

          (a) the Parent Subsidiaries shall take into account and promote the
Tax objectives of the Sub Subsidiaries, provided that, in so doing, the Parent
Subsidiaries are not adversely affected; and

          (b) the Sub Subsidiaries shall take into account and promote the Tax
objectives of the Parent Subsidiaries, provided that, in so doing, the Sub
Subsidiaries are not adversely affected.

SECTION 3.  REORGANIZATION TAXES; TAX BENEFITS
            ----------------------------------

     Section 3.1  Parent Responsible for Pre-Effective Date Taxes.
                  -----------------------------------------------

          (a) Parent shall be responsible for the payment of all Taxes of all
Sub Subsidiaries incurred with respect to periods ending on or before the
Effective Date.

          (b) With respect to any period that begins before and ends after the
Effective Date, Parent shall be responsible for the payment of all Taxes of all
Sub Subsidiaries incurred with respect to the portion of such period ending on
the Effective Date.

     Section 3.2  Parent Responsible for Reorganization Taxes.  Parent shall be
                  -------------------------------------------
responsible for the payment of all Reorganization Taxes (including
Reorganization Taxes reported on Returns filed by Sub Subsidiaries).

     Section 3.3  Reimbursement for Reorganization Tax Benefits.
                  ---------------------------------------------

          (a) The amount of the Reorganization Tax Benefit shall be calculated
at such times as Parent may reasonably request, provided, however, that it be
calculated annually.

          (b) Promptly upon the approval by Sub and Parent of the calculation
referred to in Section 3.3(a) (which approval shall not be unreasonably
withheld)--

               (I) Sub shall pay to Parent the excess (if any) of the
Reorganization Tax Benefit over the total of all payments previously made by Sub
under this Section 3.3 (net of the total of all payments previously made by
Parent under this Section 3.3), and

               (II) Parent shall pay to Sub the excess (if any) of the total of
all payments previously made by Sub under this Section 3.3 (net of the total of
all payments previously made by Parent under this Section 3.3) over the
Reorganization Tax Benefit.

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          (c)  Notwithstanding any other provision of this Section 3.3, the
total of all payments made by Sub under this Section 3.3 (net of the total of
all payments made by Parent under this Section 3.3) shall not exceed the total
of all Reorganization Taxes.

     Section 3.4  Reimbursement for Federal Utilized Tax Benefits.
                  -----------------------------------------------

          (a) The amount of the Federal Utilized Tax Benefit for any
Consolidated Return Year shall be calculated at such time as Sub may reasonably
request, provided, however, that it be calculated annually.

          (b)  Promptly upon the approval by Sub and Parent of the calculation
referred to in Section 3.4(a) (which approval shall not be unreasonably
withheld), Parent shall pay to Sub the amount (if any) of the Federal Utilized
Tax Benefit.

          (c) When any Tax Adjustment becomes final, the Federal Utilized Tax
Benefit for each affected Consolidated Return Year shall be recalculated taking
such Tax Adjustment into account.  After approval by Parent and Sub of such a
recalculation for any affected Consolidated Return Year (which approval shall
not be unreasonably withheld), Sub shall pay to Parent or Parent shall pay to
Sub (as appropriate) an amount equal to the difference between the recalculated
Federal Utilized Tax Benefit for such affected Consolidated Return Year and any
amounts previously paid with respect to such Consolidated Return Year under this
Section 3.4, together with interest thereon at the rate interest would be paid
on a Federal Income Tax overpayment (in the case of a payment by Parent to Sub)
or on a Federal Income Tax underpayment (in the case of a payment by Sub to
Parent) paid at the time of such payment.

     Section 3.5  Reimbursement for Combined Utilized Tax Benefits.  Payments
                  ------------------------------------------------
shall be made with respect to all Combined Utilized Tax Benefits, and the
calculation and recalculation of the amounts of such payments, and the approval
and timing of such payments, shall be similar to and consistent with the
procedures set out in Section 3.4.

     Section 3.6  Partial Years.  If Sub is a member of the ADL Affiliated Group
                  -------------
for less than an entire Consolidated Return Year, or if all of the Sub
Subsidiaries that are included in a Combined Return for any period are
includible for less than the entire period, the calculation of the
Reorganization Tax Benefit, Federal Utilized Tax Benefit and/or Combined
Utilized Tax Benefit (as appropriate) shall be similar to and consistent with
the procedures set out in Section 4.2.

SECTION 4.  INTERCOMPANY PAYMENTS RESPECTING FEDERAL INCOME TAXES.
            -----------------------------------------------------

     Section 4.1  Hypothetical Federal Taxes and Refunds.  For each Consolidated
                  --------------------------------------
Return Year--

          (a) Sub shall pay to Parent an amount equal to the amount of any
Federal Income Tax for which Sub would have been liable (including interest for
which Sub would have been liable, but excluding Tax penalties for which Sub
would have been liable) had Sub filed consolidated Federal Income Tax Returns
for the Sub Group, separate and apart from the Parent Group, for all periods
beginning on or after Effective Date (the "Hypothetical Federal Tax");

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          (b) Parent shall pay to Sub an amount equal to the amount of any
refund of Federal Income Tax that Sub would have received (including interest
that Sub would have received) had Sub filed consolidated Federal Income Tax
Returns for the Sub Group, separate and apart from the Parent Group, for all
periods beginning on or after the Effective Date (the "Hypothetical Federal
Refund");

          (c) the calculation of the Hypothetical Federal Tax or Hypothetical
Federal Refund shall be made by assuming that Sub made such Tax elections and
choices of methods as would most benefit the Sub Group;

          (d) the calculation of the Hypothetical Federal Tax or Hypothetical
Federal Refund shall be made by Parent and submitted to Sub for review and
approval at least 10 days prior to the Return Due Date of the Consolidated
Return for the Consolidated Return Year, and Sub's approval of such calculation
shall not be unreasonably withheld;

          (e)  except as provided in Section 4.3, all payments required by this
Section 4.1 shall be paid promptly upon the approval referred to in Section
4.1(d); provided, however, that (except as provided in Section 4.3) no such
payment shall be due prior to 3 days before the Return Due Date of the
Consolidated Return for the Consolidated Return Year; and

          (f) notwithstanding any other provision of this Section 4.1, when
calculating the Hypothetical Federal Tax or Hypothetical Federal Refund for any
Consolidated Return Year, any item which gave rise to a Federal Utilized Tax
Benefit in a prior Consolidated Return Year shall not be taken into account.

     Section 4.2  Sub Not a Member for Entire Consolidated Return Year.  If Sub
                  ----------------------------------------------------
is a member of the ADL Affiliated Group for less than the entire Consolidated
Return Year, the Hypothetical Federal Tax or Hypothetical Federal Refund shall
be calculated by hypothetically closing the books of the Sub Group as of the day
before the first day and as of the last day that Sub is a member of the ADL
Affiliated Group and taking into account only those items that accrue in that
portion of the Consolidated Return Year during which Sub is a member of the ADL
Affiliated Group, unless Sub and Parent agree otherwise.

     Section 4.3  Estimated Payments.  For each Estimated Payment Date in any
                  ------------------
Consolidated Return Year--

          (a) Parent shall calculate for the Sub Group an estimated Hypothetical
Federal Tax in a manner that is similar to and consistent with the Hypothetical
Federal Tax calculations set out in Sections 4.1 and 4.2;

          (b) Sub shall assist and cooperate with Parent in good faith and to
the extent necessary for Parent to make the calculation referred to in Section
4.3(a) reasonably accurately;

          (c) the calculation referred to in Section 4.3(a) shall be submitted
to Sub for review and approval at least 10 days prior to the related Estimated
Payment Date, and Sub's approval of such calculation shall not be unreasonably
withheld; and

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          (d) promptly upon the approval referred to in Section 4.3(c), Sub
shall pay to Parent the approved amount; provided, however, that no such payment
shall be due prior to 3 days before the related Estimated Payment Date.

     Section 4.4  Adjustments for Estimated Payments.  Amounts paid under
                  ----------------------------------
Section 4.3 shall be taken into account when calculating the payments due under
Sections 4.1 and 4.2.

     Section 4.5  Tax Adjustments.  When any Tax Adjustment made with respect to
                  ---------------
any Consolidated Return becomes final--

          (a) Parent shall promptly recalculate the Hypothetical Federal Tax or
Hypothetical Federal Refund for all affected Consolidated Return Years taking
such Tax Adjustment into account;

          (b) the recalculation referred to in Section 4.5(a) shall be promptly
submitted to Sub for review and approval, and Sub's approval of such
recalculation shall not be unreasonably withheld; and

          (c) promptly upon the approval referred to in Section 4.5(b), Sub
shall pay to Parent or Parent shall pay to Sub (as appropriate), an amount equal
to the difference between the recalculated Hypothetical Federal Tax or
recalculated Hypothetical Federal Refund and the Hypothetical Federal Tax or
Hypothetical Federal Refund, together with interest thereon at the rate interest
would be paid on a Federal Income Tax overpayment (in the case of a payment by
Parent to Sub) or on a Federal Income Tax underpayment (in the case of a payment
by Sub to Parent) paid at the time of such payment.

     Section 4.6  Estimated Federal Income Tax Underpayment Penalties. No
                  ---------------------------------------------------
intercompany payments shall be made with respect to Consolidated Tax penalties
except for penalties arising from the underpayment of estimated Consolidated
Taxes.  For each Consolidated Return Year--

          (a) Parent shall calculate for the Sub Group the amount (if any) of
the penalty for underpayment of Federal Income Taxes for which Sub would have
been liable had Sub filed consolidated Federal Income Tax Returns for the Sub
Group, separate and apart from the Parent Group, for all periods beginning on or
after the Effective Date.  Such calculation shall be made in a manner that is
consistent with the Hypothetical Federal Tax calculations set out in Sections
4.1 and 4.2;

          (b) the calculation referred to in Section 4.6(a) shall be submitted
to Sub for review and approval, and Sub's approval of such calculation shall not
be unreasonably withheld; and

          (c) promptly upon the approval referred to in Section 4.6(b), Sub
shall pay to Parent the approved amount (if any).

SECTION 5.  INTERCOMPANY PAYMENTS RESPECTING COMBINED TAXES.
            -----------------------------------------------

     Section 5.1  Payments and Calculations.  Payments between Parent and Sub
                  -------------------------
shall be made with respect to all Combined Taxes, and the calculation and
recalculation of the amounts of such payments, and the review, approval and
timing of such payments, shall be similar to and consistent with the procedures
set out in Section 4.

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     Section 5.2  Estimated Combined Tax Underpayment Penalties.  No
                  ---------------------------------------------
intercompany payments shall be made with respect to Combined Tax penalties
except for penalties arising from the underpayment of estimated Combined Taxes.
The calculation and payment of any hypothetical estimated Combined Tax
underpayment penalty shall be similar to and consistent with the procedures set
out in Section 4.6.

     Section 5.3  Definitions.  For purposes of this Agreement, the term
                  -----------
"Hypothetical Combined Tax" means an amount calculated under this Section 5 that
is payable by Sub, and the term "Hypothetical Combined Refund" means an amount
calculated under this Section 5 that is payable by Parent.

SECTION 6.  MEMBERSHIP IN AFFILIATED GROUP; CONTROL.
            ---------------------------------------

     Section 6.1  Sub Covenants.  Sub hereby covenants and agrees that it shall
                  -------------
not without Parent's consent (which may be withheld for any reason) take any
action that could result in, or fail to take any action where such failure could
result in--

          (a) Sub no longer being a member of the ADL Affiliated Group;

          (b) the Parent Group no longer being in "control" of Sub within the
meaning of Section 368(c) of the Code; or

          (c) the Parent Group including in income any "excess loss account" in
the stock of Sub under Treasury Regulations Section 1.1502-19.

     Section 6.2  Sub Indemnification.  Sub shall be responsible for, and shall
                  -------------------
indemnify and hold the Parent Group harmless from, any increase in Taxes caused
by any breach of the covenants set out in Section 6.1, including but not limited
to (i) Taxes incurred by reason of including in income any excess loss account
under Treasury Regulations Section 1.1502-19 that would not have been included
in income in the absence of such breach, (ii) Taxes incurred by reason of
including in income any deferred intercompany gain under Treasury Regulations
Section 1.1502-13 that would not have been included in income in the absence of
such breach, and (iii) Taxes incurred upon a distribution of Sub stock that
would not have been incurred in the absence of such breach.

SECTION 7.  COOPERATION.
            -----------

     Section 7.1  Cooperation Generally.  Parent and Sub agree to cooperate
                  ---------------------
fully with each other in connection with all matters subject to this Agreement.
Such cooperation includes but is not limited to--

          (a) making personnel and records available within 10 days (or such
other period as may be reasonable under the circumstances) after a request for
such personnel or records is made by the other party;

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          (b) retaining all records which may contain information or provide
evidence relevant to any open taxable period;

          (c) executing, acknowledging and delivering any instrument or document
that may be necessary or helpful in connection with (i) any Return that the
other party has the authority to prepare and file, (ii) any Tax Proceeding that
the other party has the authority to control, or (iii) the carrying out of any
obligation of the other party under this Agreement;

          (d) using best efforts to obtain any documentation from any Taxing
Authority, governmental authority or other third party that may be necessary or
helpful in connection with the foregoing; and

          (e) keeping the other party fully informed with respect to any
material developments relating to any matter subject to this Agreement.

     Section 7.2  Indemnities.  Parent agrees to indemnify and hold harmless
                  -----------
each Sub Subsidiary (and their officers and employees), and Sub agrees to
indemnify and hold harmless each Parent Subsidiary (and their officers and
employees) from any Tax attributable to the negligence or misconduct of a Parent
Subsidiary or Sub Subsidiary, as the case may be, in supplying inaccurate or
incomplete information under Section 7.1.

SECTION 8.  SPIN-OFF PROVISIONS.
            -------------------

     Section 8.1  Prior to the Parent Group engaging in a Spin-Off of Sub,
Parent and Sub shall enter into an agreement that shall include customary
provisions, covenants and indemnities, including but not limited to--

          (a) Sub's indemnity of the Parent Group for any Spin-Off tax
attributable to any act or omission of the Sub Group;

          (b) Parent's indemnity of the Sub Group for any Spin-Off tax
attributable to any act or omission of the Parent Group;

          (c) Sub's covenant not to participate in any merger, reorganization,
acquisition, equity restructuring or other transaction that results in one or
more persons acquiring in Sub a 50% or greater interest, within the meaning of
Section 355(e) of the Code, within the 4 year period beginning 2 years prior to
the Spin-Off;

          (d) Parent's covenant not to participate in any merger,
reorganization, acquisition, equity restructuring or other transaction that
results in one or more persons acquiring in Parent a 50% or greater interest,
within the meaning of Section 355(e) of the Code, within the 4 year period
beginning 2 years prior to the Spin-Off;

          (e) customary provisions regarding cooperation, exchange of
information, and control of audits and litigation respecting Taxes; and

          (f) customary provisions regarding consistency in tax return
positions.

                                       10
<PAGE>

SECTION 9.  MISCELLANEOUS.
            -------------

     Section 9.1  Survival.  No provision of the Reorganization Agreement shall
                  --------
operate so as to terminate the operation of any provision of this Agreement.
This Agreement shall survive a Spin-Off or other separation transaction except
to the extent amended by an agreement described in Section 8.1 or an amendment
described in Section 9.4.

     Section 9.2  Confidentiality.  The provisions of the Reorganization
                  ---------------
Agreement relating to confidentiality shall apply with respect to any
information obtained or learned by either party from the other party in
connection with the parties' performance of their respective obligations
hereunder.

     Section 9.3  Tax Dispute Resolution.  All Tax Disputes shall be resolved by
                  ----------------------
mutual agreement of the Tax Advisors of the disputing parties, but if with
respect to any Tax Dispute the Tax Advisors of the disputing parties cannot
reach an agreement, then the disputing parties shall appoint a mutually
agreeable Tax Advisor to resolve the Tax Dispute, and if the disputing parties
cannot agree on a Tax Advisor to so appoint, then the Tax Dispute shall be
resolved in accordance with the provisions of Section 11.3 of the Reorganization
Agreement relating to dispute resolution.

     Section 9.4  Amendment and Waiver.  The provisions of this Agreement,
                  --------------------
including, without limitation, this Section, may not be waived and this
Agreement shall not be amended or modified except in accordance with this
Section.  The provisions of this Agreement may be waived only by the written
consent of a majority of the Independent Directors of the party which is the
beneficiary of the particular provision being waived.  No failure or delay by
any party in exercising any right or remedy hereunder shall operate as a waiver
thereof, and a waiver of a particular right or remedy on one occasion shall not
be deemed a waiver of any other right or remedy or a waiver on any subsequent
occasion.  The provisions of this Agreement may be amended, modified or
supplemented only by the written consent of a majority of the Independent
Directors of each of the parties.

     Section 9.5  Notices.  Any notice to any party hereto given pursuant to
                  -------
this Agreement shall be in writing and shall be given by the means, and to the
addresses, set forth in the "Notices" section of the Reorganization Agreement.

     Section 9.6  Successors and Assigns.  This Agreement may not be assigned by
                  ----------------------
either party without the prior written consent of the other party, and any
attempt to assign any rights or obligations hereunder without such consent shall
be void.  This Agreement shall inure to the benefit of, and be binding upon and
enforceable against the respective successors and permitted assigns of the
parties hereto.

     Section 9.7  Entire Agreement; Parties in Interest.  This Agreement, the
                  -------------------------------------
schedules hereto (if any) and any applicable provisions of the Reorganization
Agreement and the Ancillary Agreements comprise the entire agreement between the
parties hereto as to the subject matter hereof and supersede all prior
agreements and understandings between them relating to the subject matter
hereof, and, except as explicitly provided, are not intended to confer upon any
person other than the parties hereto (including their successors and permitted
assigns) any rights or remedies.

                                       11
<PAGE>

     Section 9.8  Overlap with Other Agreements.  If both (i) the provisions of
                  -----------------------------
this Agreement and (ii) the provisions of the Reorganization Agreement or any
Ancillary Agreement are by their terms applicable, then both the provisions of
this Agreement and such other agreement shall apply, but if the provisions of
this Agreement and such other agreement are in conflict, then (with respect to
matters subject to this Agreement) the provisions of this Agreement shall
control.

     Section 9.9  Severability.  If any term or provision of this Agreement or
                  ------------
the application thereof to any person or circumstance shall to any extent be
invalid or unenforceable, the remainder of this Agreement or the application of
such terms or provisions to persons or circumstances other than those as to
which it is invalid or unenforceable shall not be affected thereby and each term
and provision of this Agreement shall be valid and enforced to the fullest
extent permitted by law.

     Section 9.10  Captions. Captions and headings are supplied herein for
                   --------
convenience only and shall not be deemed a part of this Agreement for any
purpose.

     Section 9.11  Governing Law.  This Agreement shall be governed by and
                   -------------
construed in accordance with the internal substantive laws of the Commonwealth
of Massachusetts, without giving effect to the principles of conflicts of laws
thereof.

     Section 9.12  Counterparts.  This Agreement may be executed in several
                   ------------
counterparts, and all counterparts so executed shall constitute one agreement,
binding upon the parties hereto, notwithstanding that the parties are not
signatory to the same counterpart.

     IN WITNESS WHEREOF, Parent and Sub have caused this Agreement to be duly
executed by their authorized representatives as an agreement under seal as of
the date first written above.

                                    PARENT:

                                    Arthur D. Little, Inc., a Massachusetts
                                    corporation

                                    By:_________________________________
                                       Name:
                                       Title:

                                    SUB:

                                    c-quential, Inc., a Delaware corporation

                                    By:_________________________________
                                       Name:
                                       Title:

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