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                                                                  Exhibit 10.15

FLEET CAPITAL CORPORATION

                                             MASTER SECURITY AGREEMENT NO. 35146

LENDER:  FLEET CAPITAL CORPORATION              CUSTOMER: DIGITAS LLC
         a Rhode Island corporation                       a MASSACHUSETTS

Address: 50 Kennedy Plaza                       Address:  800 BOYLSTON STREET
         Providence, Rhode Island 02903-2305
                                                          BOSTON, MA 02199

1. GRANT OF SECURITY INTEREST; DEFINITIONS

      Subject to the terms and conditions set forth herein (the "Master Security
Agreement") and in any Equipment Security Agreement Schedule incorporating the
terms of this Master Security Agreement (each, an "Equipment Schedule"),
Customer hereby grants to Fleet Capital Corporation ("Lender") a security
interest in and to all Collateral (hereinafter defined) in order to secure the
payment and performance of all Obligations (hereinafter defined), including but
not limited to any Obligations evidenced by one or more promissory or
installment notes which specifically refer to an Equipment Schedule (the
"Note(s)"). The extent to which Lender's security interest in any item of
Collateral shall be entitled to purchase money priority shall be determined by
reference to the unpaid principal balance of any Note evidencing the financing
of the purchase price of such item of Equipment.

      References to "the Security Agreement," "this Security Agreement" or "any
Security Agreement" shall mean and refer to any Equipment Schedule which
incorporates the terms of this Master Security Agreement, together with all
exhibits, addenda, schedules, certificates, riders and other documents and
instruments executed and delivered in connection with such Equipment Schedule,
all as the same may be amended or modified from time to time. Each Equipment
Schedule shall constitute a separate, distinct and independent security
agreement and contractual obligation of Customer. "Affiliate" means, with
respect to any person, firm or entity, any other person, firm or entity
controlling, controlled by, or under common control with such person, firm or
entity, and for this purpose, "control" means the possession, directly or
indirectly, of the power to direct or cause the direction of the management and
policies of any such person, firm or entity, whether through the legal or
beneficial ownership of voting securities, by contract or otherwise.
"Collateral" means the Equipment and all present or future additions,
attachments, accessions or accessories thereto and replacements thereof, all
tools, manuals, service records, software and similar information and materials
related to such Equipment, and the products, proceeds, offspring, rents and
profits therefrom or thereof, including proceeds in the form of goods, accounts,
chattel paper, documents, instruments and general intangibles, insurance
proceeds payable in respect of loss or damage to such Collateral, and all
returned or repossessed goods arising from or relating to any of the Collateral.
"Equipment" means machinery and equipment now owned or hereafter acquired by
Customer, wherever the same may be located, which is described in one or more
Equipment Schedules entered into from time to time by the parties hereto. The
term "item of Equipment" shall mean each functionally integrated and marketable
group or unit of Equipment; and any determination of the outstanding principal
balance of the Note with respect to any item of Equipment shall include the
unpaid total amount of all vendor or seller invoices (including Customer
invoices, if any) for such group or unit of Equipment, together with all costs
of delivery, installation, testing and related services, accessories, supplies
or attachments from vendors or supplier's thereof (including Customer provided
items) financed by Lender in connection with such group or unit of Equipment,
together with all acquisition fees and costs of delivery, installation, testing
and related services, accessories, supplies or attachments procured or financed
by Lender from vendors or suppliers thereof (including items provided by
Customer) relating to or allocable to such item of Equipment ("Related
Expenses"). "Obligations" means all indebtedness, obligations and liabilities of
Customer or any Affiliate of Customer owing to Lender of every kind and
description, direct or indirect, secured or unsecured, joint or several,
absolute or contingent, due or to become due, whether for payment or
performance, now existing or hereafter arising, regardless of how the same arise
or by what instrument, agreement or book account they may be evidenced, or
whether evidenced by any instrument, agreement or book account, including,
without limitation, all loans (including any loan by renewal or extension of
existing indebtedness or liability), all indebtedness, all obligations for the
deferred purchase price or rental of any property or of any of the Collateral,
all undertakings to take or refrain from taking any action, all indebtedness,
liabilities or obligations owing from Customer to others which may have been
obtained by purchase, negotiation, discount, transfer, assignment or otherwise,
and all interest, taxes, fees, charges, expenses and attorneys fees chargeable
to Customer or incurred by Lender under this Security Agreement, or any other
document or instrument delivered in connection herewith. As used herein with
respect to any Obligation or Equipment or Collateral: (a) the following terms
shall have the meanings or values defined or assigned to them in the applicable
Equipment Schedule therefor: "Acceptance Date," "Advance Payment(s)," "Equipment
Location(s)," "Security Deposit"; and (b) the following terms shall have the
meanings or values assigned to them in the applicable Note therefor: "Payments,"
"Payment Dates," "Maturity Date," "Interest Rate." To the extent not otherwise
specifically defined in this Master Security Agreement, unless the context
otherwise requires, all other terms contained in this Master Security Agreement
shall have the meanings assigned or referred to them in the Uniform Commercial
Code in force in the State of Rhode Island (the "UCC") to the extent the same
are used or defined therein.

2. CUSTOMER REPRESENTATIONS, WARRANTIES, COVENANTS.

      Customer hereby represents and warrants to and covenants with Lender that,
as of the date hereof and for so long as any Obligations shall remain
outstanding: (a) Customer is duly organized and is existing in good standing
under the laws of its jurisdiction of organization and is duly qualified and in
good standing in those jurisdictions where the conduct of its business or the
ownership of its properties requires qualification; (b) Customer has the power
and authority to own the Collateral, to enter into and perform this Security
Agreement and any other document or instrument delivered in connection herewith
and to incur the Obligations; (c) Customer's chief executive office is located
at the address set forth above; (d) Customer utilizes no trade names in the
conduct of its business; (e) Customer has not changed its name, been the
surviving entity in a merger, acquired any business; or changed the location of
its chief executive office within the previous five years, except as may have
been specifically disclosed to Lender in writing prior to the date hereof; (f)
the execution and performance of this Security Agreement, the Notes and any
other document or instrument delivered in connection herewith will not result in
the creation or imposition of any lien or encumbrance upon any of the
Collateral, except in favor of Lender pursuant hereto; (g) this Security
Agreement, the Notes and any document or instrument delivered in connection
herewith and the transactions contemplated hereby or thereby are duly
authorized, executed and delivered, and this Security Agreement, the Notes and
such other documents and instruments constitute valid and legally binding
obligations of Customer and are enforceable against Customer in accordance with
their respective terms; (h) Customer has filed all federal, state and local tax
returns and other reports it is required to file and has paid or made adequate
provision for payment of all such taxes, assessments and other governmental
charges; (i) there are no pending or threatened actions or proceedings before
any court or administrative agency which materially adversely affect Customer's
financial condition or operations; (j) no representation, warranty or statement
by Customer contained herein or in any certificate or other document furnished
or to be furnished by Customer pursuant hereto contains or at the time of
delivery shall contain any untrue statement of material fact, or omits, or shall
omit at the time of delivery, to state a material fact necessary to make it not
misleading; (k) Customer shall furnish Lender: (i) within 120 days after tile
last day of each fiscal year of Customer, a financial statement including a
balance sheet, income statement, statement of retained earnings and a statement
of cash flows, each prepared in accordance with generally accepted accounting
principles consistently applied with a report signed by an independent certified
public accountant satisfactory to Lender; (ii) upon the request of Lender,
within 45 days after the close of each quarter of each fiscal year of Customer,
financial statements similar to those described in the immediately preceding
clause, prepared by Customer and certified by the chief financial officer of
Customer; (iii) promptly upon request of Lender, in form satisfactory to Lender,
such other and additional information as Lender may reasonably request from time
to time; (l) Customer shall permit Lender, through its authorized attorneys,
accountants and representatives, to inspect and examine the Collateral and the
books, accounts, records, ledgers and assets of every kind and description of
Customer with respect thereto at all reasonable times; (ml Customer shall
promptly inform Lender of any Defaults (defined below) or any events or changes
in the financial condition of Customer occurring since the date of the last
financial statements of Customer delivered to Lender which, individually or
cumulatively, when viewed in light of prior financial statements, may result in
a material adverse change in the financial condition of Customer; (n)


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Customer shall pay or deposit promptly when due all sales, use, excise, personal
property, income, withholding, corporate, franchise and other taxes. assessments
and governmental charges upon or relating to its ownership or use of any of the
Collateral and submit to Lender proof satisfactory to Lender that such payments
and/or deposits have been made; (o) if Customer shall now or hereafter maintain
an employee benefit plan covered by Section 4021(a) of the Employee Retirement
Income Security Act of 1974 ("ERISA") relating to plan termination insurance,
Customer is not aware as of the date hereof, and shall promptly notify Lender
hereafter upon notice or knowledge of: (i) the filing of notice with the Pension
Benefit Guaranty Corporation (the "PBGC") pursuant to Section 4041 of ERISA that
such plan is to be terminated; and (ii) the institution of proceedings by the
PBGC under Section 4042 of ERISA; (p) Customer shall at any time and from time
to time upon request of Lender, execute and deliver to Lender, in form and
substance satisfactory to Lender, such documents as Lender shall deem necessary
or desirable to perfect or maintain perfected the security interest of Lender in
the Collateral or which may be necessary to comply with the provisions of the
law of any jurisdiction in which Customer may then be conducting business or in
which any of the Collateral may be located.

3. COLLATERAL REPRESENTATIONS, WARRANTIES, COVENANTS

      Customer hereby further represents and warrants to and covenants with
Lender that, as of the date hereof and for so long as any Obligations shall
remain outstanding: (a) Customer is the owner of the Collateral free and clear
of all rights, title, security interests, encumbrances or liens of any other
party, and Customer will defend the Collateral against all claims and demands of
all persons at any time claiming any interest therein; (b) the Equipment is
personal property even though the Equipment may hereafter become attached or
affixed to real property; (c) the equipment location(s), if not owned by
Customer, are leased by Customer pursuant to valid leases or rental agreements
which permit the possession, use and operation of the Equipment at said
locations; (d) Customer shall provide Lender with disclaimers and waivers from
landlords, mortgagees and other persons holding any interest or claim in and to
any Equipment location or any Collateral, acceptable in all respects to Lender,
which may be necessary or advisable in the sole discretion of Lender to confirm
that the first priority security interest and rights of Lender in the Collateral
are and will remain valid against all other parties; (e) the Equipment is in the
possession of Customer at the equipment location(s) specified in the applicable
Equipment Schedules therefor, and shall not be removed therefrom without the
prior written consent of Lender, which consent shall in any event be conditioned
upon Customer having completed all notifications, filings, recordings, and other
actions in such new location as Lender may require to protect and perfect
Lender's interests in the Collateral; (f) Customer shall not, without the prior
written consent of Lender, sell, offer to sell, lease, rent, hire or in any
other manner dispose, transfer or surrender use and possession of any Equipment;
(g) Customer will not, directly or indirectly, create, incur or permit to exist
any lien, encumbrance, mortgage, pledge, attachment or security interest on or
with respect to the Equipment except in favor of Lender under the terms of this
Security Agreement; (h) Customer shall deliver to Lender any and all evidence of
ownership of, and certificates of title to, any and all of the Equipment; (i)
Customer shall permit each item of Equipment to be used only within the
continental United States by qualified personnel solely for business purposes
and the purpose for which it was designed and, at its sole expense, shall
service, repair, overhaul and maintain each item of Equipment in the same
condition as when received, ordinary wear and tear excepted, in good operating
order, consistent with prudent industry practice (but, in no event less than the
same extent to which Customer maintains other similar equipment in the prudent
management of its assets and properties) and in compliance with all applicable
laws, ordinances, regulations, and conditions of all insurance policies required
to be maintained by Customer under the Security Agreement and all manuals,
orders, recommendations, instructions and other written requirements as to the
repair and maintenance of such item of Equipment issued at any time by the
vendor and/or manufacturer thereof; (j) Customer shall furnish to Lender such
information concerning the condition, location, use and operation of the
Equipment as Lender may request; (k) Customer shall permit any parson designated
by Lender to visit and inspect any item of Equipment and any records maintained
in connection therewith, provided, however, that the failure of Lender to
inspect the Equipment or to inform Customer of any noncompliance shall not
relieve Customer of any of its Obligations hereunder; (l) if any item of
Equipment does not comply with the requirements of this Security Agreement,
Customer shall, within 30 days of written notice from Lender, bring such
Equipment into compliance with the provisions hereof; and (m) Customer shall not
use any Equipment, nor allow the same to be used, for any unlawful purpose, nor
in connection with any property or material that would subject the Lender to any
liability under any state or federal statute or regulation pertaining to the
production, transport, storage, disposal or discharge of hazardous or toxic
waste or materials.

4. SELECTION AND USE OF EQUIPMENT; DISCLAIMER OF WARRANTIES

      Customer has selected each item of Equipment and the manufacturer and/or
supplier thereof based on its own judgment, and expressly disclaims any reliance
upon any statements or representations made by Lender. If the Equipment is not
delivered, is not properly installed, does not operate as warranted by the
manufacturer or supplier thereof, becomes obsolete, or is unsatisfactory for any
reason whatsoever, Customer shall make all claims on account thereof solely
against the manufacturer or supplier thereof and not against Lender. Customer
acknowledges that neither the manufacturer or supplier of the Equipment, nor any
sales representative or agent thereof, is an agent of Lender, and no agreement
or representation as to the Equipment or any other matter by any such sales
representative or agent of the manufacturer or supplier shall in any way affect
any of the Notes or the Obligations.

      LENDER IS NOT THE MANUFACTURER OR SUPPLIER OF THE EQUIPMENT, NOR THE AGENT
THEREOF, AND MAKES NO EXPRESS OR IMPLIED REPRESENTATIONS OR WARRANTIES AS TO ANY
MATTER WHATSOEVER, INCLUDING WITHOUT LIMITATION, THE MERCHANTABILITY OF THE
EQUIPMENT, ITS FITNESS FOR A PARTICULAR PURPOSE, ITS DESIGN OR CONDITION, ITS
CAPACITY OR DURABILITY, THE QUALITY OF THE MATERIAL OR WORKMANSHIP IN THE
MANUFACTURE OR ASSEMBLY OF THE EQUIPMENT, OR THE CONFORMITY OF THE EQUIPMENT TO
THE PROVISIONS AND SPECIFICATIONS OF ANY PURCHASE ORDER RELATING THERETO, OR
PATENT INFRINGEMENTS, AND LENDER HEREBY DISCLAIMS ANY SUCH WARRANTY. LENDER IS
NOT RESPONSIBLE FOR ANY REPAIRS OR SERVICE TO THE EQUIPMENT, DEFECTS THEREIN OR
FAILURES IN THE OPERATION THEREOF.

5. RISK OF LOSS AND DAMAGE; INSURANCE

      Customer assumes all risk of loss, damage or destruction to the Equipment
from whatever cause and for whatever reason. If all or a portion of an item of
Equipment shall become lost, stolen, destroyed, damaged beyond repair or
rendered permanently unfit for use for any reason, or in the event of any
condemnation, confiscation, theft or seizure or requisition of title to or use
of such item, Customer shall immediately pay to Lender an amount equal to the
outstanding principal balance of the applicable Note with respect to such item
of Equipment as of the next following Payment Date, plus all accrued interest
and other charges then due and owing hereunder and under the Note. For so long
as any Obligations shall remain outstanding, Customer shall procure and maintain
insurance in such amounts and with such coverages, and upon such terms and with
such companies, as Lender may approve, at Customer's expense, provided, however,
that in no event shall such insurance be less than the following coverages and
amounts: (a) Worker's Compensation and Employer's Liability Insurance, in the
full statutory amounts provided by law; (b) Comprehensive General Liability
Insurance including product/completed operations and contractual liability
coverage, with minimum limits of the greater of: (i) $1,000,000 each occurrence,
and Combined Single Limit Bodily Injury and Property Damage, $1,000,000
aggregate, where applicable, or (ii) as otherwise specified in any Equipment
Schedule hereto; and (c) All Risk Physical Damage Insurance, including
earthquake and flood, on each item of Equipment, in an amount not less than the
greater of (i) the outstanding principal balance owing under any Note with
respect to such the Equipment; or (ii) its full replacement value. On each such
policy Lender will be included as an additional insured and loss payee as its
interest may appear. Such policies shall be endorsed to provide that the
coverage afforded to Lender shall not be rescinded, impaired or invalidated by
any act or neglect of Customer. Customer agrees to waive Customer's rights and
its insurance carrier's rights of subrogation against Lender for any and all
loss or damage. In addition to the foregoing minimum insurance coverage,
Customer shall procure and maintain such other insurance coverage as Lender may
require. All policies shall be endorsed or contain a clause requiring the
insurer to furnish Lender with at least 30 days' prior written notice of any
material change, cancellation or non-renewal of coverage. Upon execution of this
Security Agreement, Customer shall furnish Lender with a certificate of
insurance or other evidence satisfactory to Lender that such insurance coverages
are in effect, provided, however, that Lender shall be under no duty either to
ascertain the existence of or to examine such insurance coverage or to advise
Customer in the event such insurance coverage should not comply with the
requirements hereof. If Customer shall at any time or times hereafter fail to
obtain and/or maintain any of the policies of insurance required herein, or fail
to pay any premium in whole or in part relating to any such policies, Lender
may, but shall not be obligated to, obtain and/or cause to be maintained
insurance coverage with respect to the Collateral, including, at Lender's
option, the coverage provided by all or any of the policies of Customer and pay
all or any part of the premium therefor, without waiving any Event of Default by
Customer, and any sums so disbursed by Lender shall be additional Obligations of
Customer to Lender payable on demand. Lender shall have the right to settle and
compromise any and all claims under any of the policies required to be
maintained by Customer hereunder and Customer hereby appoints


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Lender as its attorney-in-fact, with power to demand, receive and receipt for
all monies payable thereunder, to execute in the name of Customer or Lender or
both any proof of loss, notice, draft or other instruments in connection with
such policies or any loss thereunder and generally to do and perform any and all
acts as Customer, but for this appointment, might or could perform.

6. EVENTS OF DEFAULT

      An "Event of Default" under any Security Agreement shall be deemed to have
occurred upon the occurrence or existence of any one or more of the following
events or conditions (each a "Default") and after the giving of any required
notice or the passage of any required period of time (or both) specified below
with respect to such Default: (a) Customer shall fail to make any Payment due
under any Note within 10 days of its due date; or (b) Customer shall fail to
obtain or maintain any of the insurance required under any Security Agreement;
or (c) Customer shall fail to perform or observe any covenant, condition or
agreement under any Security Agreement, and such failure continues for 10 days
after notice thereof to Customer; or (d) Customer or any Affiliate of Customer
shall default in the payment or performance of any Obligation owing to Lender,
or any indebtedness or obligation owing to any Affiliate of Lender, under any
note, security agreement, equipment lease, title retention or conditional sales
agreement or any instrument or agreement evidencing such indebtedness with
Lender or any such Affiliate of Lender; or (e) any representation or warranty
made by Customer herein or in any certificate, agreement, statement or document
hereto or hereafter furnished Lender, including without limitation any financial
information disclosed to Lender, shall prove to be false or incorrect in any
material respect; or (f) death or judicial declaration of incompetence of
Customer, if an individual; or (g) the commencement of any bankruptcy,
insolvency, arrangement, reorganization, receivership liquidation or other
similar proceeding by or against Customer or any of its properties or
businesses, or the appointment of a trustee, receiver, liquidator or custodian
for Customer or any of its properties or businesses, or if Customer suffers the
entry of an order for relief under Title 11 of the United States Code; or (h)
the making by Customer of a general assignment or deed of trust for the benefit
of creditors; or (i) Customer shall default in any payment or other obligation
to any third party and any applicable grace or cure period with respect thereto
has expired; or (j) Customer shall terminate its existence by merger,
consolidation, sale of substantially all of its assets or otherwise; or (k) if
Customer is a privately held entity, more than the 50% of Customer's voting
capital stock or equivalent ownership interest, or effective control of such
stock or interest in Customer, issued and outstanding from time to time, is not
retained by the holders of such stock or interest on the date of this Security
Agreement; or (l) if Customer is a publicly held corporation, there shall be a
change in the ownership of Customer's stock such that Customer is no longer
subject to the reporting requirements of the Securities Exchange Act of 1934 or
no longer has a class of equity securities registered under Section 12 of the
Securities Act of 1933; or (m) Lender shall determine, in its sole discretion
and in good faith, that there has been a material adverse change in the
financial condition of the Customer since the date of this Master Security
Agreement, or that Customer's ability to perform its Obligations is impaired; or
(n) any event or condition set forth in subsections (b) through (m) of this
Section 6 shall occur with respect to any guarantor or other person liable or
responsible, in whole or in part, for payment or performance of any Obligations;
or (o) any event or condition set forth in subsections (e) through (l) shall
occur with respect to any Affiliate of Customer. Customer shall promptly notify
Lender of the occurrence of any Event of Default or the occurrence or existence
of any event or condition, which, upon the giving of notice of lapse of time, or
both, would constitute an Event of Default.

7. RIGHTS AND REMEDIES; MANDATORY PREPAYMENT

      Upon the occurrence of an Event of Default, Lender shall have all of the
rights and remedies enumerated herein (all of which are cumulative and not
exclusive of any other right or remedy available to Lender): (a) Lender may
declare, at its option, all or any part of the Obligations immediately due and
payable, without demand, notice of intention to accelerate, notice of
acceleration, notice of nonpayment, presentment, protest, notice of dishonor, or
any other notice whatsoever, all of which are hereby waived by Customer and any
endorser, guarantor, surety or other party liable in any capacity for any of the
Obligations; (b) Lender shall have the right to enter and/or remain upon the
Equipment Location(s) without any obligation to pay rent to Customer or others,
or any other place or places where any of the Collateral is located and kept
and: (i) remove Collateral therefrom to the premises of Lender or any agent of
Lender, for such time as Lender may desire, in order to maintain, collect, sell
and/or liquidate the Collateral; (ii) use such premises, together with
materials, supplies, books and records of Customer, to maintain possession
and/or the condition of the Collateral, and to prepare the Collateral for
selling, liquidating or collecting; or (iii) without removing the Collateral
from such premises, render the Collateral unusable by the Customer or by any
other party in possession thereof or with an interest therein; (c) Lender may
require Customer to assemble the Collateral and make it available to Lender at a
place to be designated by Lender; (d) Lender shall have the right to set-off,
without notice to Customer, any and all deposits or other sums at any time or
times credited by or due from Lender, to Customer, whether in a special account
or other account or represented by a certificate of deposit (whether or not
matured) which deposits and other sums shall at all times constitute additional
security for the Obligations and may be set-off against all or any part of the
Obligations; and (e) Lender shall have, in addition to any other rights and
remedies contained in this Security Agreement and any other agreements,
guarantees, notes, instruments and documents heretofore, now or at any time or
times hereafter executed by Customer and delivered to Lender, all of the rights
and remedies of a secured party under the UCC. If Lender seeks to take
possession of any or all of the Collateral by court process, Customer hereby
irrevocably waives any bonds and any surety or security relating thereto
required by any statute, court rule or otherwise as an incident to such
possession, and waives any demand for possession prior to the commencement of
any suit or action to recover with respect thereto. Any notice required to be
given by Lender of a sale or other disposition or other intended action by
Lender with respect to any of the Collateral or otherwise which is made in
accordance with the terms of this Security Agreement at least five (5) days
prior to such proposed action, shall constitute fair and reasonable notice to
Customer of any such action. Lender shall be liable to Customer only for its
gross negligence or willful misconduct in falling to comply with any applicable
law imposing duties upon Lender; Lender's liability for any such failure shall
be limited to the actual loss suffered by Customer directly resulting from such
failure; and in no event shall Lender have any liability to Customer for
incidental, consequential, punitive or exemplary damages. All expenses of
retaking, holding, preparing for sale, selling or the like and any other
expenses incurred by Lender in connection with the exercise of any of its rights
and remedies in hereunder shall constitute additional Obligations secured by the
Collateral hereunder. If Lender shall employ counsel to commence, defend or
intervene, file a petition, complaint, answer, motion or other pleadings, or to
take any other action in or with respect to any suit or proceeding (bankruptcy
or otherwise) relating to this Agreement, the Collateral or any other agreement,
guaranty, note, instrument or document heretofore, now or at any time or times
hereafter executed by Customer and delivered to Lender, or to protect, collect,
lease, sell, take possession of or liquidate any of the Collateral, or to
attempt to enforce or to enforce any security interest in any of the Collateral,
or to enforce any rights of Lender hereunder, whether before or after the
occurrence of any Event of Default, or to collect any of the Obligations, then
in any of such events, all of the reasonable attorneys, fees arising from such
services, and any expenses, costs and charges relating thereto, shall be part of
the Obligations, payable on demand and secured by the Collateral. The net
proceeds realized by Lender upon any sale or other disposition of Collateral
hereunder shall be applied toward satisfaction of all Obligations until all such
Obligations are satisfied and paid in full. Lender shall account to Customer for
any surplus realized upon such sale or other disposition, and Customer shall
remain liable for any deficiency. The commencement of any action, legal or
equitable, shall not affect the security interest of Lender in the Collateral
until all of the Obligations or any judgment with respect thereto have been
fully paid.

      Customer is or may become indebted under or in respect of one or more
leases, loans, notes, credit agreements, reimbursement agreements, security
agreements, title retention or conditional sales agreements, or other documents,
instruments or agreements, whether now existing or hereafter arising, evidencing
Customer's obligations for the payment of borrowed money or other financial
accommodations owing to Lender and/or one or more affiliated persons, firms or
entities controlling, controlled by or under common control with Lender
("Affiliated Obligations"). If Customer pays or prepays all or substantially all
of its Affiliated Obligations, whether or not such payment or prepayment is
voluntarily or involuntarily made by Customer before or after any default or
acceleration of such Affiliated Obligations, then Customer shall pay, at
Lender's option and immediately upon notice from Lender, all or any part of
Customer's Obligations owing to Lender, including but not limited to payment of
the accelerated balance of one or more Notes as set forth in such notice from
Lender.

8. ASSIGNMENT

      The provisions of this Agreement shall be binding upon and shall inure to
the benefit of the heirs, administrators, successors and assigns of Lender and
Customer, provided, however, Customer may not assign any of its rights or
delegate any of its obligations hereunder without the prior written consent of
Lender. Lender may, from time to time, without notice to the Customer, sell,
assign, transfer, participate, pledge or otherwise dispose of all or any part of
the Obligations and/or the Collateral therefor. In such event, each and every
immediate and successive purchaser, assignee, transferee, participant, pledgee,
or holder of all or any part of the Obligations and/or the Collateral (each, a
"Holder") shall have the right to enforce this Agreement, by legal action


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or otherwise, for its own benefit as fully as if such Holder were herein by name
specifically given such rights. Customer agrees that the rights of any such
Holder hereunder or with respect to the related Obligations, shall not be
subject to any defense, set off or counterclaim that Customer may assert or
claim against Lender, and that any such Holder shall have all of the Lender's
rights hereunder but none of the Lender's obligations. Lender shall have an
unimpaired right to enforce this Agreement for its benefit with respect to that
portion of the Obligations Lender has not sold, assigned, transferred,
participated, pledged or otherwise disposed of.

9. GOVERNING LAW

      THIS SECURITY AGREEMENT AND THE LEGAL RELATIONS OF THE PARTIES HERETO
SHALL IN ALL RESPECTS BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS
OF THE STATE OF RHODE ISLAND, WITHOUT REGARD TO PRINCIPLES REGARDING THE CHOICE
OF LAW. CUSTOMER HEREBY CONSENTS AND SUBMITS TO THE JURISDICTION OF THE COURTS
OF THE STATE OF RHODE ISLAND AND THE FEDERAL DISTRICT COURT FOR THE DISTRICT OF
RHODE ISLAND FOR THE PURPOSES OF ANY SUIT, ACTION OR OTHER PROCEEDING ARISING
OUT OF ITS OBLIGATIONS HEREUNDER, AND EXPRESSLY WAIVES ANY OBJECTIONS THAT IT
MAY HAVE TO THE VENUE OF SUCH COURTS. CUSTOMER HEREBY EXPRESSLY WAIVES ANY RIGHT
TO TRIAL BY JURY IN ANY ACTION BROUGHT ON OR WITH RESPECT TO THIS SECURITY
AGREEMENT. Any action by Customer against Lender for any cause of action under
this Security Agreement shall be brought within one year after any such cause of
action first arises.

10. MISCELLANEOUS, GENERAL PROVISIONS.

      Customer agrees to pay on demand all costs and expenses of Lender
(including reasonable attorneys' fees) hereafter incurred in connection with the
amendment or modification of any Security Agreement, or any other or additional
documentation or transactions concerning the Obligations, or the care, custody,
administration, perfection or protection of any of the Collateral or any of
Lender's rights or interests therein, including, without limitation, any and all
fees and charges for searches of lien records or other public records, and any
filing, stamp and other taxes or fees payable or determined to be payable in
connection with the execution, delivery, filing, and recording of any UCC
financing statements or other recorded instrument. Customer shall execute and
deliver to Lender upon Lender's request any and all schedules, forms and other
reports and information as Lender may deem necessary or appropriate to respond
to requirements or regulations imposed by any governmental authorities. Customer
shall execute and deliver to Lender upon Lender's request such further and
additional documents, instruments and assurances as Lender deems necessary (a)
to acknowledge and confirm for the benefit of Lender or any Holder, all of the
terms and conditions of all or any part of the Obligations, this Security
Agreement and Lender's or Holder's rights with respect thereto and Customer's
compliance with all of the terms and provisions of any Obligations, and (b) to
preserve, protect and perfect Lender's or Holder's right, title or interest in
any Obligation or Collateral, including, without limitation, such UCC financing
statements or amendments, corporate resolutions, opinions of counsel,
certificates of compliance, notices of assignment or transfers of interests, and
restatements and reaffirmation of all Obligations and Customer's representations
and warranties with respect thereto as of the dates requested by Lender from
time to time. Lender may file or record this Security Agreement or a memorandum
or a photocopy thereof (which for the purposes hereof shall be effective as a
financing statement) so as to give notice to third parties, and Customer hereby
appoints Lender as its attorney-in-fact to execute, sign, file and record UCC
financing statements and other lien recordation documents with respect to the
Equipment, and Customer agrees to pay or reimburse Lender for any and all
filing, recording or stamp fees or taxes arising from any such filings.

THIS SECURITY AGREEMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES
CONCERNING LENDER'S RIGHTS AND SECURITY INTERESTS IN THE COLLATERAL AND
CONSTITUTES THE ENTIRE AGREEMENT BETWEEN THE PARTIES, SUPERSEDING ANY AND ALL
CONFLICTING TERMS OR PROVISIONS OF ANY PRIOR PROPOSALS, COMMITMENT LETTERS, TERM
SHEETS OR OTHER AGREEMENTS OR UNDERSTANDINGS BETWEEN THE PARTIES. THIS SECURITY
AGREEMENT MAY NOT BE CONTRADICTED BY EVIDENCE OF (i) ANY PRIOR, WRITTEN OR ORAL
AGREEMENTS OR UNDERSTANDINGS OR (ii) ANY CONTEMPORANEOUS OR SUBSEQUENT ORAL
AGREEMENTS OR UNDERSTANDINGS BETWEEN THE PARTIES, AND CUSTOMER ACKNOWLEDGES AND
CERTIFIES THAT NO SUCH ORAL OR WRITTEN AGREEMENTS OR UNDERSTANDINGS EXIST AS OF
THE DATE OF THIS SECURITY AGREEMENT. THIS SECURITY AGREEMENT MAY NOT BE AMENDED,
NOR MAY ANY RIGHTS UNDER THE SECURITY AGREEMENT BE WAIVED, EXCEPT BY AN
INSTRUMENT IN WRITING SIGNED BY THE PARTY CHARGED WITH SUCH AMENDMENT OR WAIVER.
The failure of Lender at any time or times hereafter to require strict
performance by Customer of any of the provisions, warranties, terms and
conditions contained in this Security Agreement or in any other agreement,
guaranty, note, instrument or document now or at any time or times hereafter
executed by Customer and delivered to Lender shall not waive, affect or diminish
any right of Lender at any time or times hereafter to demand strict performance
thereof. No rights of Lender hereunder shall be deemed to have been waived by
any act or knowledge of Lender, its agents, officers or employees, unless such
waiver is contained in an instrument in writing signed by an officer of Lender
and directed to Customer specifying such waiver. No waiver by Lender of any of
its rights on one occasion shall operate as a waiver of any other of its rights
or any of its rights on a future occasion. This Master Security Agreement will
not be binding on Lender until accepted and executed by Lender, notice of which
is hereby waived by Customer. Any demand or notice required or permitted to be
given hereunder shall be deemed effective when deposited in the United States
mail, and sent by certified mail, return receipt requested, postage prepaid,
addressed to Lender or to Customer at the addresses set forth herein, or to such
other address as may be hereafter provided by the party to be notified by
written notice complying with the provisions hereof. Wherever possible, each
provision of this Security Agreement shall be interpreted in such manner as to
be effective and valid under applicable law. Should any portion of this Security
Agreement be declared invalid for any reason in any jurisdiction, such
declaration shall have no effect upon the remaining portions of this Agreement;
furthermore, the entirety of this Security Agreement shall continue in full
force and effect in all other jurisdictions and said remaining portions of this
Security Agreement shall continue in full force and effect in the subject
jurisdiction as if this Security Agreement had been executed with the invalid
portions thereof deleted. This Security Agreement may be executed in any number
of counterparts, each of which shall be deemed to be an original, but all of
which together shall constitute but one and the same instrument. Time is of the
essence in the payment and performance of all of the Obligations. The section
headings herein are included for convenience only and shall not be deemed to be
a part of this Security Agreement. Each reference herein to "Lender" shall be
deemed to include its successors and assigns, and each reference to "Customer"
and any pronouns referring thereto as used herein shall be construed in the
masculine, feminine, neuter, singular or plural, as the context may require, and
shall be deemed to include the legal representatives, successors and assigns of
Customer, all of whom shall be bound by the provisions hereof. EACH REFERENCE
HEREIN TO "CUSTOMER" SHALL MEAN AND INCLUDE ANY AND ALL CUSTOMERS WHO SIGN
BELOW, EACH OF WHOM SHALL BE JOINTLY AND SEVERALLY LIABLE UNDER THE SECURITY
AGREEMENT.

Executed and delivered by duly authorized representatives of the parties hereto
as of the date set forth below.

Dated as of: SEPTEMBER 27, 2000

FLEET CAPITAL CORPORATION                   DIGITAS LLC


By:                                         By:    /s/ Marschall Smith
       ----------------------------                -----------------------------
Name:                                       Name:  MARSCHALL SMITH
       ----------------------------                -----------------------------
Title:                                      Title: General Counsel
       ----------------------------                -----------------------------
                                            Customer's Taxpayer ID #: 04-2712533
                                                                      ----------


<PAGE>

                                   Rider No. 1
                     to Master Security Agreement No. 35146
                                   Dated as of
                                September 27, 2000

            This Rider No. 1 (the "Rider") is entered into as of September 27,
2000, between Fleet Capital Corporation ("Lender") and Digitas LLC ("Customer"),
and amends that certain Master Equipment Security Agreement dated as of
September 27, 2000, including any riders and equipment schedules thereto (the
"Master Security Agreement") between Lender and Customer. All capitalized terms
used in this Rider shall, unless otherwise indicated, have the definitions set
forth in the Master Security Agreement.

            IN CONSIDERATION OF the mutual covenants and promises as hereinafter
set forth, Lender and Customer hereby agree as follows:

      1. Add the following to the end of Section 2

            "(q) Customer's sole subsidiaries as of the date of this Master
Security Agreement are Bronner Slosberg, Humphrey Co., BSH HOLDING LLC, and
Digitas, Inc. and Customer shall not acquire or organize any other subsidiary
unless Customer shall have given Lender prior written notice thereof and
provided to Customer a guarantee, in form and substance acceptable to Lender, of
such new subsidiary guarantying the payment and performance by documents and
agreements as Lender may reasonably request."

      2. The following new Section 2A is hereby added to the Master Security
Agreement:

            "5A.1 All of the terms, covenants and agreements set forth in
Section 11 of that certain Revolving Credit Agreement, dated as of July 25,
2000, by and between Digitas LLC as Borrower, Digitas Inc., Bronner Slosberg
Humphrey Co., and BSH Holding LLC as Guarantors and Fleet National Bank as Bank,
as in effect on the date hereof (the "Credit Agreement") are hereby incorporated
by reference as if the same had been set forth herein in full. Any amendments or
modifications to, or replacements of, any such terms, covenants and agreements
made between Customer and the Bank shall not be binding upon Lender unless
approved by Lender in writing. All such terms, covenants and agreements shall
survive the ( expiration or other termination of the Credit Agreement. For
purposes of this Section 5.A, "Bank" shall mean "Lender" and the "Credit
Agreement" shall mean the "Master Security Agreement." All other terms
incorporated pursuant to this Section LA and not otherwise defined shall have
the meanings set forth in the Credit Agreement.

            5A.2. In the event the Credit Agreement has expired or has been
terminated prior to the expiration or other termination of the Master Security
Agreement, Customer agrees to continue to provide to Lender, concurrently with
the financial statements required pursuant to Credit Agreement, the certificates
of compliance substantially In the form required pursuant to the Credit
Agreement as it pertains to the covenants incorporated pursuant to Section 5.A
above."

      3. The terms and conditions of this Rider shall prevail where there may be
conflicts or inconsistencies with the terms and conditions of the Master
Security Agreement.

            IN WITNESS WHEREOF, Lendor and Customer, by their duly authorized
representatives, have duly executed and delivered this Rider which is intended
to take effect as a sealed instrument as of the date of the Master Security
Agreement.

FLEET CAPITAL CORPORATION                   DIGITAS LLC


By:                                         By:    /s/ Marschall Smith
       ----------------------------                -----------------------------
Title:                                      Title: MARSCHALL SMITH
       ----------------------------                -----------------------------
                                                   General Counsel