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                                                                   Exhibit 10.18

                                PLEDGE AGREEMENT

This is a pledge agreement made as of the 14th day of March, 2000 between
Lawrence P. Begley, an individual residing at Walpole, Massachusetts ("Pledgor")
and CCBN.COM, a Delaware corporation ("Pledgee").

                                   WITNESSETH:

WHEREAS, the Pledgor has issued a secured promissory note (the "Note") of even
date herewith in the original principal amounts of Five-Hundred Ninety-Nine
Thousand Nine Hundred Ninety-Two and 92/100 ($599,992.90) Dollars payable to the
Pledgee; and

WHEREAS, as collateral security for the obligations of the Pledgor under the
Note, the Pledgor has agreed to pledge and grant to the Pledgee a first priority
security interest in certain shares which the Pledgor owns in the Pledgee, as
more fully set forth herein;

NOW THEREFORE, the parties hereto agree and acknowledge that the foregoing
recitals are true and correct and to the following:

      1. Pledge of Collateral. As collateral security for the performance of the
obligations of the Pledgor under the Note (the "Obligations"), the Pledgor
hereby pledges and grants to the Pledgee a security interest in and to 111,730
shares of the Class A Common Stock of the Company held by the Pledgor, as
identified in Exhibit A annexed hereto, and any and all stock rights, powers and
other distributions, dividends or proceeds thereof (the "Shares"). In addition,
any stock rights, dividends, powers or other distributions or proceeds received
by the Pledgor shall be held in trust for and delivered to the Pledgee to be
held in accordance with the terms of this Agreement, and shall be included in
the Shares described above.

      2. Delivery of the Shares. The Shares have been delivered to the Pledgee
on the date hereof, together with undated stock powers executed in blank. Upon
payment in full of the Note, the Pledgee shall return to the Pledgor the Shares,
undated stock powers as well as such other instruments, documents, stock
certificates, money and goods as may come into Pledgee's possession from time to
time, whether through delivery by Pledgor or otherwise.

      3. Pledgee's Rights and Duties with Respect to the Collateral. Pledgee's
only duty with respect to the Shares shall be to exercise reasonable care to
secure the safe custody thereof all other duties being hereby expressly
disclaimed. Pledgee shall have the right, but not the obligation, to (a) demand,
sue for, receive and collect all money or money damages payable on account of
any Shares, (b) protect, preserve or assert any other rights of Pledgor or take
any other action with respect to the Shares, and (c) pay any taxes, liens,
assessments, insurance premiums or other charges pertaining to Shares. Any
expenses incurred by Pledgee under the preceding sentence shall be paid by
Pledgor upon demand, become part of the Obligations secured by the Shares and
bear interest at the rate of 18% per annum until paid. Pledgee shall be relieved
of all responsibility for the Shares upon surrendering them to Pledgor.

      4. Pledgor's Warranties and Indemnity.
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            4.1 Pledgor represents, warrants and covenants (a) that Pledgor is
the lawful owner of the Shares, (b) that the Shares are fully paid and
nonassessable, (c) that as of the date hereof, the Shares are free and clear of
all liens, encumbrances, and security interests, and this pledge constitutes a
valid and perfected security interest in the Shares enforceable against the
Pledgor, (d) that the Shares are not subject to any outstanding rights of
redemption or options to purchase or sell except as set forth in the Company's
Certificate of Incorporation and By-laws, (e) that the Pledgor has the sole
right and lawful authority to pledge the Shares and otherwise to comply with the
provisions hereof, (f) no litigation is pending or threatened against the
Pledgor, which if adversely determined, would have a material adverse effect
against the Pledgor or the Pledgee's rights in respect of the Shares, (g) that
the Pledgor agrees to defend the Pledgee's title in the Shares and the security
interest therein against any and all claims and demands, and (h) this Agreement
constitutes the legal, valid and binding obligation of the Pledgor, enforceable
against the Pledgor in accordance with its terms.

            4.2 If any adverse claim is asserted in respect of the Shares or any
portion thereof, except as such may arise from the wanton, reckless or
unauthorized acts of the Pledgee, the Pledgor agrees to indemnify the Pledgee
and hold the Pledgee harmless from and against any reasonable liabilities or
damages, and reasonable attorney's fees incurred by the Pledgee in exercising
any right, power or remedy of the Pledgee hereunder. Any such loss, liability or
expense so incurred shall be paid by the Pledgor upon demand, become part of the
Obligations secured by the Shares and bear interest at the rate of 18% per
annum.

      5. Voting of Collateral. While Pledgor is not in default hereunder,
Pledgor may vote the Shares, provided that said voting shall be in conformity
with the Pledgor's performance under this Agreement and the Notes.

      6. Dividends and Other Distributions. While Pledgor is not in default
hereunder, Pledgor may receive all cash dividends, payments of principal and
interest, and other distributions payable with respect to Shares, provided,
however, that Pledgor shall immediately inform Pledgee of the receipt of any
such dividend, payment or other distribution and shall hold the amount thereof
in trust for Pledgee unless and until Pledgee shall in writing release Pledgor
from such trust. Pledgor shall cause all non-cash dividends and distributions
with respect to Shares to be distributed directly to Pledgee, to be held by
Pledgee as additional Shares, and if any such distribution is made to Pledgor he
shall receive such distribution in trust for Pledgee and shall immediately
transfer it to Pledgee.

      7. Pledgor's Default. Pledgor shall be in default hereunder upon the
occurrence of any of the following events:

            (a) Any event of default shall occur under the Note;

            (b) If Pledgor is not paying his debts as they become due, becomes
insolvent, files or has filed against him a petition under any chapter of the
United States Bankruptcy Code, 11 U.S.C. ss. 101 et seq. (or any similar
petition under any insolvency law of any jurisdiction), proposes any
liquidation, composition or financial reorganization with his creditors, makes
an assignment or trust mortgage for the benefit of creditors, or if a receiver,
trustee, custodian or


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similar agent is appointed or takes possession with respect to any property or
business of Pledgor;

            (c) If any lien, encumbrance or adverse claim of any nature
whatsoever is asserted with respect to any Shares;

            (d) If any warranty of Pledgor hereunder is or shall become false;

            (e) If Pledgor fails to fulfill any obligation hereunder;

            (f) If Pledgor fails to pay or perform any of the Obligations when
such payment of performance is due.

      8. Pledgee's Rights upon Default. Upon the occurrence of any default as
defined in Section 7 hereof, Pledgee may, if Pledgee so elects in its sole
discretion, take any one or more of the following:

            (a) at any time and from time to time sell, assign and deliver all
or any part of the Shares, or any interest therein, at any public or private
sale, for cash, on credit or for other property, for immediate or future
delivery without any assumption of credit risk, and for such price or prices and
on such terms as Pledgee in its absolute discretion may determine; provided that
(i) at least ten (10) days' notice of the time and place of any such sale shall
be given to Pledgor, and (ii) in the case of any private sale, such notice shall
also contain the terms of the proposed sale and Pledgee shall sell the
Collateral proposed to be sold to any purchaser procured by Pledgor who is
ready, willing and able to purchase, and who prior to the time of such sale
tenders the purchase price of, such Collateral on terms more favorable to
Pledgee than the terms contained in such notice; provided, further, the Pledgor
acknowledges that the Pledgee may be unable to effect a public sale of all or
part of the Shares by reason of certain prohibitions contained in the Securities
Act of 1933, as amended, and may be compelled to resort to one or more private
sales to a restricted group of purchasers who will be obligated to agree, among
other things, to acquire such securities for their own account, for investment,
and not with a view to the distribution or resale thereof. The Pledgor
acknowledges that any such private sale may be at prices and on terms less
favorable to the seller than if sold at public sales and that private sales
shall be deemed to be made in a commercially reasonable manner notwithstanding
that such a private sale may result in a lower sale price.

            (b) exercise the right to vote, the right to receive cash dividends
and other distributions, and all other rights with respect to the Collateral as
though Pledgee were the absolute owner thereof, whether or not such rights were
retained by Pledgor as against Pledgee before default; and

            (c) exercise all other rights available to a secured party under the
Uniform Commercial Code and other applicable law.

            (d) the rights and remedies available pursuant to the Agreement are
cumulative, and not exclusive of any other rights or remedies otherwise
available to the Pledgee.


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      9. Application of Sale Proceeds. In the event of a sale of Shares, the
proceeds shall first be applied to the payment of the expenses of the sale,
including brokers' commissions, counsel fees, any taxes or other charges imposed
by law upon the Shares or the transfer thereof and all other charges paid or
incurred by Pledgee pertaining to the sale; and, second, to satisfy outstanding
Obligations, in the order in which Pledgee elects in its sole discretion; and,
third, the surplus (if any) shall be paid to Pledgor.

      10. Notices. All notices made or required to be made hereunder shall be
sent by United States first class or certified or registered mail, with postage
prepaid, or delivered by hand to Pledgee or to Pledgor at the addresses first
above written. Notice by mail shall be deemed to have been made on the date when
the notice is deposited in the mail.

      11. Heirs, Successors, Etc. This Agreement and all of its terms and
provisions shall benefit and bind the heirs, successors, assigns, transferees,
executors and administrators of each of the parties hereto.

      12. Pledgee's Forbearance. Any forbearance, failure or delay by Pledgee in
exercising any right, power or remedy hereunder shall not be deemed a waiver of
such right, power or remedy. Any single or partial exercise of any right, power
or remedy of Pledgee shall continue in full force and effect until such right,
power or remedy is specifically waived in writing by Pledgee.

      13. Further Assurances. The Pledgor covenants and agrees to execute and
deliver, or cause to be executed or delivered, all such other stock powers,
proxies, instruments, and documents, and will take such other action or actions
as the Pledgee may reasonably request from time to time in order to carry out
the provisions and purposes hereof.

      14. Termination. This Agreement and the pledge and security interest
represented hereby shall terminate upon the indefeasible payment in full of the
Note.

      15. Miscellaneous. (a) This Agreement or any part thereof cannot be
changed, waived, or amended except by an instrument in writing signed by
Pledgee; and waiver on one occasion shall not operate as a waiver on any other
occasion. (b) The Uniform Commercial Code and other laws of the Commonwealth of
Massachusetts shall govern the construction and enforcement of this Agreement.
(c) If any part of this Agreement or any agreement, document, or instrument
executed in connection herewith shall be deemed invalid or unenforceable by a
court of competent jurisdiction, the remaining provisions shall remain in full
force and effect, and shall continue to be binding upon the parties. (d) This
Agreement may be executed in one or more counterparts, each of which shall
constitute an original, but all of which, when taken together, shall constitute
one and the same instrument.

      16. Jurisdiction. The Pledgor irrevocably submits to the jurisdiction of
the courts of the Commonwealth of Massachusetts and the United States District
Court for the District of Massachusetts for the purpose of any suit, action or
other proceeding brought by the Lender arising out of or relating to this
Agreement, and the Pledgor waives and agrees not to assert by way of motion, as
a defense or otherwise in any such suit, action or proceeding, any claim that
the Pledgor is not personally subject to the jurisdiction of the courts of the
Commonwealth of


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Massachusetts or the United States District Court for the District of
Massachusetts or that the Pledgor's property is exempt or immune from execution
or attachment, either prior to judgment or in aid of execution, that the suit,
action or proceeding is brought in an inconvenient forum or that the venue of
the suit, action or proceeding is improper, or that this Pledge Agreement or the
subject matter hereof may not be enforced in or by such court.

THE PLEDGOR HEREBY WAIVES ANY AND ALL RIGHTS TO A TRIAL BY JURY IN ANY ACTION OR
PROCEEDING IN CONNECTION WITH ALL MATTERS CONTEMPLATED HEREBY AND DOCUMENTS
EXECUTED IN CONNECTION HEREWITH.

      EXECUTED under seal as of the date first above written.

      PLEDGOR:

      /s/ Lawrence P. Begley
      _________________________________
      Lawrence P. Begley


      PLEDGEE:
      CCBN.COM, Inc.


      By: /s/ Jeffrey P. Parker
          _____________________________
          Jeffrey P. Parker
          Chairman of the Board
           and CEO


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