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                                                                   Exhibit 10.24

                       SIXTH AMENDMENT TO CREDIT AGREEMENT
                       AND AMENDMENT TO SECURITY DOCUMENTS

     This SIXTH AMENDMENT TO CREDIT AGREEMENT AND AMENDMENT TO SECURITY
DOCUMENTS (this "Amendment") is dated as of November 30, 2001, and is entered
into by and between Opinion Research Corporation, a Delaware corporation
("Parent"), ORC INC., a Delaware corporation ("ORC", Parent and ORC are
sometimes collectively referred to herein as the "Borrowers" and individually as
a "Borrower"), the Subsidiaries of Borrowers party hereto, Heller Financial,
Inc., in its capacity as Agent for the Lenders party to the Credit Agreement
described below ("Agent"), and the Lenders which are signatories hereto.

     WHEREAS, Agent, Lenders and Borrower are parties to a certain Credit
Agreement dated as of May 26, 1999 (as such agreement has from time to time been
amended, supplemented or otherwise modified, the "Agreement"); and

     WHEREAS, the parties desire to amend the Agreement as hereinafter set
forth.

     NOW THEREFORE, in consideration of the mutual conditions and agreements set
forth in the Agreement and this Amendment, and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto hereby agree as follows:

     1.   Definitions. Capitalized terms used in this Amendment, unless
otherwise defined herein, shall have the meaning ascribed to such terms in the
Agreement.

     2.   Amendments to Agreement. Subject to the conditions set forth below,
the Agreement is amended as follows:

          (a)  Subsection 3.4(G) of the Agreement is amended in its entirety and
as so amended shall read as follows:

          "(G) foreign exchange contracts and interest rate protection
agreements entered into in the ordinary course of business consistent with past
practices for bona fide hedging purposes and not for speculation (provided, that
notwithstanding anything to the contrary contained in this Agreement, the
notional amount of all Interest Rate Hedge Agreements shall not exceed
$45,000,000); and"

          (b)  Subsection 6.3 of the Agreement is amended by inserting the
following parenthetical immediately after the word "Obligations" in each
instance such word appears in such subsection:

          "(other than Obligations arising under any Interest Rate Hedge
     Agreement)"

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          (c)  Subection 9.2 of the Agreement is hereby amended by inserting the
following parenthetical immediately after the word "Loan Documents" in the first
instance such word appears in such subsection:

          "(other than any Interest Rate Hedge Agreement, the provisions of
     which shall be amended, modified, terminated or waived in accordance with
     its terms; provided, that any amendment, modification or waiver of any
     provision of an Interest Rate Hedge Agreement that is adverse to the
     interests of Borrowers or any Lender shall be consented to by Requisite
     Lenders)"

          (d)  The definition of "Loan Document" contained in subsection 10.1 of
the Agreement is hereby amended in its entirety and as so amended shall read as
follows:

          "Loan Documents" means this Agreement, the Notes, the Security
     Documents, any Interest Rate Hedge Agreement and all other instruments,
     documents and agreements by or on behalf of any Loan Party and delivered
     concurrently herewith or at any time hereafter to or for the benefit of
     Agent or any Lender in connection with the Loans and other transactions
     contemplated by this Agreement, all as amended, supplemented or modified
     from time to time; but excluding all Capitalization/Acquisition Documents.

          (e)  Subsection 10.1 of the Agreement is further amended by adding
thereto the following definitions in the correct alphabetical order:

          "Hedge Counterparty" means the Lender (or any affiliate of such
Lender) party to an Interest Rate Hedge Agreement with Borrowers.

          "Interest Rate Hedge Agreement" means a swap agreement (as such term
     is defined in Section 101 of the Bankruptcy Code) between Borrowers and a
     Lender and any other agreements or arrangements entered into in connection
     therewith designed to provide protection against fluctuations in interest
     rates, the form, substance, terms and conditions of which have been
     consented to in writing by Agent, which consent shall not be unreasonably
     withheld.

     3.   Amendment to Security Documents. Subject to the conditions set forth
below and after giving effect to the amendments to the Agreement set forth
above, the Security Documents are amended as follows:

          (a)  To the extent any of the Security Documents grant Liens to Agent
for the benefit of Agent and Lenders, each such Security Document is hereby
amended to provide that such Lien is granted for the benefit of Agent, the
Lenders and any Hedge Counterparty; provided, however, that the maximum
aggregate dollar amount of Obligations that Borrowers owe at any

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one time under all Interest Rate Hedge Agreements then in effect that shall be
secured by the Collateral shall not exceed $1,500,000.

          (b)  To the extent secured by the Collateral in accordance with the
immediately preceding clause (a), for purposes of Section 14 of that certain
Security Agreement dated as of May 26, 1999 among Parent, ORC and Agent, and
Section 14 of that certain Subsidiary Security Agreement dated as of May 26,
1999 among Agent and the direct and indirect Subsidiaries of Borrowers from time
to time party thereto, all Obligations outstanding under any Interest Rate Hedge
Agreement shall share in the proceeds of any sale of, or other realization upon,
all or any part of the Collateral on a pari passu basis with the principal
amounts of the Secured Obligations.

     4. Conditions. The effectiveness of this Amendment is subject to the
following conditions precedent:

          (a)  Borrower shall have executed and delivered this Amendment, and
such other documents and instruments as Agent may require shall have been
executed and/or delivered to Agent;

          (b)  All proceedings taken in connection with the transactions
contemplated by this Amendment and all documents, instruments and other legal
matters incident thereto shall be satisfactory to Agent and its legal counsel;

          (c)  No Default or Event of Default shall have occurred and be
continuing; and

          (d)  The representations and warranties set forth in Section 5 below
are true, correct and complete.

     5.   Representations and Warranties. To induce Agent and Lenders to enter
into this Amendment, each of the Borrowers represents and warrants to Agent and
Lenders:

          (a)  that the execution, delivery and performance of this Amendment
has been duly authorized by all requisite corporate action on the part of such
Borrower and that this Amendment has been duly executed and delivered by such
Borrower; and

          (b)  that each of the representations and warranties set forth in
Section 5 of the Agreement (other than those which, by their terms, specifically
are made as of certain date prior to the date hereof) are true and correct in
all material respects as of the date hereof.

     6.   Severability. Any provision of this Amendment held by a court of
competent jurisdiction to be invalid or unenforceable shall not impair or
invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

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     7.   References. Any reference to the Agreement contained in any document,
instrument or agreement executed in connection with the Agreement shall be
deemed to be a reference to the Agreement as modified by this Amendment.

     8.   Counterparts. This Amendment may be executed in one or more
counterparts, each of which shall constitute an original, but all of which taken
together shall be one and the same instrument.

     9.   Ratification. The terms and provisions set forth in this Amendment
shall modify and supersede all inconsistent terms and provisions of the
Agreement and shall not be deemed to be a consent to the modification or waiver
of any other term or condition of the Agreement. Except as expressly modified
and superseded by this Amendment, the terms and provisions of the Agreement are
ratified and confirmed and shall continue in full force and effect.

     10.  Reaffirmation. Each Loan Party party hereto has executed and delivered
one or more of the Security Documents and/or the other Loan Documents as debtor,
grantor, pledgor, guarantor, assignor, or in other similar capacities in which
such Person has granted liens or security interests in their respective
properties or otherwise acted as an accommodation party or guarantor, as the
case may be. Each Loan Party party hereto hereby ratifies and reaffirms all of
its respective payment and performance obligations, contingent or otherwise,
under the Security Documents and any other Loan Documents to which it is a party
and, to the extent any such Person has granted liens on or security interests in
any of their respective properties pursuant to any of the Security Documents or
any of the other Loan Documents as security for or otherwise guaranteed the
Obligations under or with respect to the Agreement or any other Loan Documents,
hereby ratifies and reaffirms such payment and performance obligations,
guarantee and grant of security interests and liens and confirms and agrees that
such security interests and liens hereafter secure all of the Obligations. Each
Loan Party party hereto agrees that each of the Security Documents and each
other Loan Document remains in full force and effect and is hereby ratified and
reaffirmed, and agrees that the Amendment shall not (i) operate as a waiver of
any right, power or remedy of Agent or Lenders under the Loan Documents or (ii)
constitute a waiver of any provision of any of the Loan Documents or serve to
effect a novation of the Obligations.

         [rest of page intentionally left blank; signature page follows]

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed under seal and delivered by their respective duly authorized
officers on the date first written above.

AGENT and LENDERS:                             BORROWERS:

HELLER FINANCIAL, INC.,                        OPINION RESEARCH CORPORATION,
as Agent and as a  Lender                      a Delaware corporation

By:  /s/ Francois Delangle                     By:  /s/ Douglas L. Cox
   -----------------------------------            ------------------------------
Name:    Francois Delangle                     Name:    Douglas L. Cox
     ---------------------------------              ----------------------------
Title:   Vice President                        Title:   Secretary
      --------------------------------               ---------------------------

FIRST UNION NATIONAL BANK,                     ORC INC.,
as a Lender                                             a Delaware corporation

By:  /s/ John L. Thomas                        By:  /s/ Kevin P. Croke
   -----------------------------------            ------------------------------
Name:    John L. Thomas                        Name:    Kevin P. Croke
     ---------------------------------              ----------------------------
Title:   Vice President                        Title:   President
      --------------------------------               ---------------------------

FLEET NATIONAL BANK,
as a Lender

By:  /s/ Thomas Hamilton
   -----------------------------------
Name:    Thomas Hamilton
     ---------------------------------
Title:   Assistant Vice President
      --------------------------------

MERRILL LYNCH BUSINESS FINANCIAL SERVICES, INC.,
as a Lender

By:  /s/ Valerie Wilder Moore
   -----------------------------------
Name:    Valerie Wilder Moore
     ---------------------------------
Title:   Assistant Vice President
      --------------------------------

PNC BANK, NATIONAL ASSOCIATION,
as a Lender

By:  /s/ Jefferey A. Blakemore
   -----------------------------------
Name:    Jefferey A. Blakemore
     ---------------------------------
Title:   Senior Vice President
      --------------------------------

                       [signatures continued on next page]

Sixth Amendment to Credit Agreement and
Amendment to Security Documents

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SUBSIDIARIES:

ORC TELESERVICE CORP.,
a Delaware corporation

By:  /s/ Kevin P. Croke
   -----------------------------------
Name:    Kevin P. Croke
     ---------------------------------
Title:   Secretary
      --------------------------------


ORC PROTEL, INC.,
a Delaware corporation

By:  /s/ Kevin P. Croke
   -----------------------------------
Name:    Kevin P. Croke
     ---------------------------------
Title:   Secretary
      --------------------------------


MACRO INTERNATIONAL, INC.,
a Delaware corporation

By:  /s/ Douglas L. Cox
   -----------------------------------
Name:    Douglas L. Cox
     ---------------------------------
Title:   Secretary
      --------------------------------


SOCIAL AND HEALTH SERVICES, LTD.,
a Maryland corporation

By:  /s/ Kevin P. Croke
   -----------------------------------
Name:    Kevin P. Croke
     ---------------------------------
Title:   Secretary
      --------------------------------


ORC CONSUMER, INC.,
a Delaware corporation

By:  /s/ Kevin P. Croke
   -----------------------------------
Name:    Kevin P. Croke
     ---------------------------------
Title:   Secretary
      --------------------------------

Sixth Amendment to Credit Agreement and
Amendment to Security Documents