<PAGE>   1

                                                  Registration No. 333-


                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                      Charles River Associates Incorporated
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)


        Massachusetts                                         04-2372210
-------------------------------                            ----------------
(State or other jurisdiction of                            (I.R.S. Employer
 incorporation or organization)                           Identification No.)


200 Clarendon Street, Boston, Massachusetts                      02116
-------------------------------------------                     -------
(Address of principal executive offices)                       (Zip Code)

                      CHARLES RIVER ASSOCIATES INCORPORATED
                1998 INCENTIVE AND NONQUALIFIED STOCK OPTION PLAN
                            (Full title of the plan)

                                James C. Burrows
                      Charles River Associates Incorporated
                              200 Clarendon Street
                           Boston, Massachusetts 02116
                                 (617) 425-3000
                      --------------------------------------
                          (Name and address, including
              telephone number and area code, of agent for service)

                                 WITH A COPY TO:
                           Peter M. Rosenblum, Esquire
                             Foley, Hoag & Eliot LLP
                             One Post Office Square
                           Boston, Massachusetts 02109
                                 (617) 832-1000

--------------------------------------------------------------------------------
                         CALCULATION OF REGISTRATION FEE
================================================================================
                                                       Proposed
    Title of                          Proposed         Maximum
   Securities         Amount          Maximum         Aggregate       Amount of
      to be            to be      Offering Price      Offering      Registration
   Registered       Registered       Per Share         Price             Fee
--------------------------------------------------------------------------------

Common Stock          326,000        $18.50 (1)     $6,031,000 (1)    $1,780 (1)
(without par value)   shares

Common Stock          644,000        $23.82 (2)    $15,340,080 (2)    $4,526 (2)
(without par value)
================================================================================

<PAGE>   2

         (1) For shares issuable pursuant to stock options outstanding on
September 9, 1998, calculated pursuant to Rule 457(h) based on the exercise
price of these options.
        
         (2) Estimated pursuant to Rule 457(c) and (h) based on the average of
the high and low prices of the Common Stock as reported on the National
Association of Securities Dealers Automated Quotation National Market System on
September 9, 1998.

                   -------------------------------------------





<PAGE>   3

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         The following documents filed with the Securities and Exchange
Commission (the "Commission") are incorporated in this Registration Statement by
reference:

         (a) the Prospectus dated April 23, 1998 of Charles River Associates
Incorporated (the "Company" or the "Registrant") included in the Company's
Registration Statement on Form S-1, File No. 333-46941, as declared effective by
the Commission on April 23, 1998;

         (b) the description of the Company's Common Stock contained in the
Registration Statement on Form 8-A filed with the Commission on April 23, 1998
under Section 12 of the Securities Exchange Act of 1934, including any amendment
or report filed for the purpose of updating such description;

         (c) the Company's quarterly report on Form 10-Q filed with the
Commission on June 26, 1998 under Section 13 of the Securities Exchange Act of
1934, as amended.

         All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended,
prior to the filing of a post-effective amendment which indicates that all
securities offered have been sold or which deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this
Registration Statement and to be part hereof from the date of filing of such
documents.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         The validity of the securities registered hereby is being passed upon
for the Company by Foley, Hoag & Eliot LLP, Boston, Massachusetts.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Article 6 of the Company's Amended and Restated Articles of
Organization provides that no director shall be personally liable to the Company
or its stockholders for monetary damages for breach of fiduciary duty as a
director of the Company to the maximum extent permitted by Massachusetts law.
Section 13(b)(1 1/2) of Chapter 156B of the Massachusetts General Laws (the
"Massachusetts Business Corporation Law") provides that the articles of
organization of a corporation may state a provision eliminating or limiting the
personal liability of a director to a corporation or its stockholders for
monetary damages for breach of fiduciary duty as a director, provided, however,
that such provision shall not eliminate or limit the liability of a director (i)
for any breach of the director's duty of loyalty to the corporation or its
stockholders, (ii) for acts of omissions not in good faith or which involve
intentional misconduct or knowing violation of law, (iii) under


<PAGE>   4

section 61 or 62 of the Massachusetts Business Corporation Law dealing with
liability for unauthorized distributions and loans to insiders, respectively,
or (iv) for any transaction from which the director derived an improper
personal benefit.

         Article 6 of the Company's Amended and Restated Articles of
Organization further provides that the Company shall, to the fullest extent
authorized by the Massachusetts Business Corporation Law, indemnify each person
who is, or shall have been, a director or officer of the Company or who is or
was a director or employee of the Company and is serving, or shall have served,
at the request of the Company, as director or officer of another organization or
in any capacity with respect to any employee benefit plan of the Company,
against all expense, liability and loss (including, but not limited to,
attorneys' fees, judgments, fines, ERISA excise taxes or penalties and amounts
paid in settlement) reasonably incurred or suffered by any such person in
connection with, or arising out of, any action, suit or proceeding, whether
civil, criminal, administrative, investigative or otherwise in which they may be
involved by reason of being or having been such a director or officer or as a
result of service with respect to any such employee benefit plan. Section 67 of
the Massachusetts Business Corporation Law authorizes a corporation to indemnify
its directors, officers, employees and other agents unless such person shall
have been adjudicated in any proceeding not to have acted in good faith in the
reasonable belief that such action was in the best interest of the corporation
or, to the extent such matter related to service with respect to an employee
benefit plan, in the best interests of the participants or beneficiaries of such
employee benefit plan.

         The effect of these provisions would be to permit indemnification by
the Company for, among other liabilities, liabilities arising out of the
Securities Act of 1933, as amended.

         Section 67 of the Massachusetts Business Corporation Law also affords a
Massachusetts corporation the power to obtain insurance on behalf of its
directors and officers against liabilities incurred by them in those capacities.
The Company has procured a directors' and officers' liability and company
reimbursement liability insurance policy that (i) insures directors and officers
of the Company against losses (above a deductible amount) arising from certain
claims made against them by reason of certain acts done or attempted by such
directors or officers and (ii) insures the Company against losses (above a
deductible amount) arising from any such claims, but only if the Company is
required or permitted to indemnify such directors or officers for such losses
under statutory or common law or under provisions of the Company's Amended and
Restated Articles of Organization or Restated By-Laws.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

ITEM 8.  EXHIBITS.

4.1      Amended and Restated Articles of Organization of the Company (filed
         as Exhibit 3.2 to the Company's registration statement on Form S-1,
         File No. 333-46941, and incorporated herein by reference).


                                      II-2

<PAGE>   5


4.2      Amended and Restated By-Laws of the Company (filed as Exhibit 3.4
         to the Company's registration statement on Form S-1, File No.
         333-46941, and incorporated herein by reference).

4.3      Charles River Associates Incorporated 1998 Incentive and Nonqualified
         Stock Option Plan (filed as Exhibit 10.1 to the Company's registration
         statement on Form S-1, File No. 333-46941, and incorporated herein by
         reference).

5.1      Opinion of Foley, Hoag & Eliot LLP.

23.1     Consent of Ernst & Young LLP, Independent Auditors.

23.2     Consent of Foley, Hoag & Eliot LLP (included in Exhibit 5.1).

24.1     Power of Attorney (contained on the signature page).

ITEM 9.  UNDERTAKINGS.

         1. The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

         2. The undersigned registrant hereby undertakes:

              (a) To file, during any period in which offers or sales are
being made, a post-effective amendment to this registration statement:

                (i) To include any  prospectus  required by Section  10(a)(3) 
              of the Securities Act of 1933;

                (ii) To reflect in the prospectus any facts or events
              arising after the effective date of the registration statement
              (or the most recent post-effective amendment thereof) which,
              individually or in the aggregate, represent a fundamental
              change in the information set forth in the registration
              statement. Notwithstanding the foregoing, any increase or
              decrease in volume of securities offered (if the total dollar
              value of securities offered would not exceed that which was
              registered) and any deviation from the low or high end of the
              estimated maximum offering range may be reflected in the form
              of prospectus filed with the Commission pursuant to Rule
              424(b) if, in the aggregate, the changes in volume and price
              represent no more than 20 percent change in the maximum
              aggregate offering price set forth in the "Calculation of
              Registration Fee" table in the effective registration
              statement.

                                      II-3

<PAGE>   6


                (iii) To include any material information with
              respect to the plan of distribution not previously disclosed
              in the Registration Statement or any material change to such
              information in the Registration Statement;

provided, however, that paragraphs 2 (a)(1)(i) and 2 (a)(1)(ii) do not apply if
the information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed with or furnished to the
Commission by the registrant pursuant to Section 13 or 15(d) of the Securities
Exchange Act of 1934 that are incorporated by reference herein.

              (b) That, for the purpose of determining any liability under
the Securities Act of 1933, each such post-effective amendment shall be deemed
to be a new registration statement relating to the securities offered therein,
and the offering of such securities at that time shall be deemed to be the
initial bona fide offering thereof.

              (c) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

         3.   Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the registrant pursuant to the foregoing provisions, or otherwise,
the registrant has been advised that in the opinion of the Securities and
Exchange Commission such indemnification is against public policy as expressed
in the Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
registrant of expenses incurred or paid by a director, officer or controlling
person of the registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Act and will
be governed by the final adjudication of such issue.

                                      II-4


<PAGE>   7


                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the city of Boston, Commonwealth of Massachusetts, on this 15th
day of September, 1998.

                                 CHARLES RIVER ASSOCIATES INCORPORATED



                                 By:/s/ JAMES C. BURROWS
                                    --------------------
                                        James C. Burrows
                                        President


                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS that each individual whose signature
appears below constitutes and appoints James C. Burrows, Laurel E. Morrison and
Firoze E. Katrak, and each of them, his true and lawful attorneys-in-fact and
agents with full power of substitution, for him and in his name, place and
stead, in any and all capacities, to sign any and all amendments (including
post-effective amendments) to this registration statement, and to file the same,
with all exhibits thereto, and all documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorneys-in-fact and
agents, and each of them, full power and authority to do and perform each and
every act and thing which they, or any of them, may deem necessary or advisable
to be done in connection with this registration statement, as fully to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorneys-in-fact and agents or any of them, or any
substitute or substitutes for any or all of them, may lawfully do or cause to be
done by virtue hereof.

         Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the dates indicated.



Signature                    Title                           Date
----------                   -----                           ----

/s/ FRANKLIN  M.FISHER       Chairman of the Board           September 15, 1998
----------------------                                              
    Franklin M. Fisher


/s/ JAMES C. BURROWS         President, Cheif Executive      September 15, 1998
--------------------         Officer and Director                    
    James C. Burrows         (principal executive officer)  

                                      II-5



<PAGE>   8




 Signature                                  Title                     Date
 --------                                   -----                     ----

/s/ LAUREL E. MORRISON         Chief Financial Officer,       September 15, 1998
----------------------         Vice President, Finance and 
    Laurel E. Morris           Administration,and Treasurer                     
                               (principal financial and
                               accounting officer



/s/ FIROZE E. KATRAK           Vice President and Director    September 15, 1998
--------------------
    Firoze E. Katrak


/s/ WILLIAM B. BURNETT         Vice President and Director    September 15, 1998
----------------------
    William B. Burnett


/s/ CARL KAYSEN                Director                       September 15, 1998
---------------                                                                
    Carl Kaysen


/s/ ROWLAND T. MORIARTY        Director                       September 15, 1998
-----------------------                                           
    Rowland T. Moriarty

                                      II-6




<PAGE>   9



                                  EXHIBIT INDEX
                         
Exhibit
  No.             Description

4.1               Amended and Restated Articles of Organization of the
                  Company (filed as Exhibit 3.2 to the Company's registration
                  statement on Form S-1, File No. 333-46941, and incorporated
                  herein by reference).

4.2               Amended and Restated By-Laws of the Company (filed as
                  Exhibit 3.4 to the Company's registration statement on Form
                  S-1, File No. 333-46941, and incorporated herein by
                  reference).

4.3               Charles River Associates Incorporated 1998 Incentive and
                  Nonqualified Stock Option Plan (filed as Exhibit 10.1 to the
                  Company's registration statement on Form S-1, File No.
                  333-46941, and incorporated herein by reference).

5.1               Opinion of Foley, Hoag & Eliot LLP.

23.1              Consent of Ernst & Young LLP, independent auditors.

23.2              Consent of Foley, Hoag & Eliot LLP (included in Exhibit 5.1).

24.1              Power of Attorney (contained on the signature page).
[{"type": "S-8", "sequence": "1", "description": "CHARLES RIVER ASSOCIATES", "secsgml_size_bytes": 20005}]
{"company-data": {"conformed-name": "CHARLES RIVER ASSOCIATES INC", "cik": "0001053706", "assigned-sic": "8742", "irs-number": "042372210", "state-of-incorporation": "MA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-63451", "film-number": "98709949"}, "business-address": {"street1": "200 CLARENDON STREET", "street2": "T-33", "city": "BOSTON", "state": "MA", "zip": "02116", "phone": "6174253000"}}
1

                                                  Registration No. 333-

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                      Charles River Associates Incorporated
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)

        Massachusetts                                         04-2372210
-------------------------------                            ----------------
(State or other jurisdiction of                            (I.R.S. Employer
 incorporation or organization)                           Identification No.)

200 Clarendon Street, Boston, Massachusetts                      02116
-------------------------------------------                     -------
(Address of principal executive offices)                       (Zip Code)

                      CHARLES RIVER ASSOCIATES INCORPORATED
                1998 INCENTIVE AND NONQUALIFIED STOCK OPTION PLAN
                            (Full title of the plan)

                                James C. Burrows
                      Charles River Associates Incorporated
                              200 Clarendon Street
                           Boston, Massachusetts 02116
                                 (617) 425-3000
                      --------------------------------------
                          (Name and address, including
              telephone number and area code, of agent for service)

                                 WITH A COPY TO:
                           Peter M. Rosenblum, Esquire
                             Foley, Hoag & Eliot LLP
                             One Post Office Square
                           Boston, Massachusetts 02109
                                 (617) 832-1000

--------------------------------------------------------------------------------
                         CALCULATION OF REGISTRATION FEE
================================================================================
                                                       Proposed
    Title of                          Proposed         Maximum
   Securities         Amount          Maximum         Aggregate       Amount of
      to be            to be      Offering Price      Offering      Registration
   Registered       Registered       Per Share         Price             Fee
--------------------------------------------------------------------------------

Common Stock          326,000        $18.50 (1)     $6,031,000 (1)    $1,780 (1)
(without par value)   shares

Common Stock          644,000        $23.82 (2)    $15,340,080 (2)    $4,526 (2)
(without par value)
================================================================================
2

         (1) For shares issuable pursuant to stock options outstanding on
September 9, 1998, calculated pursuant to Rule 457(h) based on the exercise
price of these options.
        
         (2) Estimated pursuant to Rule 457(c) and (h) based on the average of
the high and low prices of the Common Stock as reported on the National
Association of Securities Dealers Automated Quotation National Market System on
September 9, 1998.

                   -------------------------------------------
3

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         The following documents filed with the Securities and Exchange
Commission (the "Commission") are incorporated in this Registration Statement by
reference:

         (a) the Prospectus dated April 23, 1998 of Charles River Associates
Incorporated (the "Company" or the "Registrant") included in the Company's
Registration Statement on Form S-1, File No. 333-46941, as declared effective by
the Commission on April 23, 1998;

         (b) the description of the Company's Common Stock contained in the
Registration Statement on Form 8-A filed with the Commission on April 23, 1998
under Section 12 of the Securities Exchange Act of 1934, including any amendment
or report filed for the purpose of updating such description;

         (c) the Company's quarterly report on Form 10-Q filed with the
Commission on June 26, 1998 under Section 13 of the Securities Exchange Act of
1934, as amended.

         All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended,
prior to the filing of a post-effective amendment which indicates that all
securities offered have been sold or which deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this
Registration Statement and to be part hereof from the date of filing of such
documents.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         The validity of the securities registered hereby is being passed upon
for the Company by Foley, Hoag & Eliot LLP, Boston, Massachusetts.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Article 6 of the Company's Amended and Restated Articles of
Organization provides that no director shall be personally liable to the Company
or its stockholders for monetary damages for breach of fiduciary duty as a
director of the Company to the maximum extent permitted by Massachusetts law.
Section 13(b)(1 1/2) of Chapter 156B of the Massachusetts General Laws (the
"Massachusetts Business Corporation Law") provides that the articles of
organization of a corporation may state a provision eliminating or limiting the
personal liability of a director to a corporation or its stockholders for
monetary damages for breach of fiduciary duty as a director, provided, however,
that such provision shall not eliminate or limit the liability of a director (i)
for any breach of the director's duty of loyalty to the corporation or its
stockholders, (ii) for acts of omissions not in good faith or which involve
intentional misconduct or knowing violation of law, (iii) under
4

section 61 or 62 of the Massachusetts Business Corporation Law dealing with
liability for unauthorized distributions and loans to insiders, respectively,
or (iv) for any transaction from which the director derived an improper
personal benefit.

         Article 6 of the Company's Amended and Restated Articles of
Organization further provides that the Company shall, to the fullest extent
authorized by the Massachusetts Business Corporation Law, indemnify each person
who is, or shall have been, a director or officer of the Company or who is or
was a director or employee of the Company and is serving, or shall have served,
at the request of the Company, as director or officer of another organization or
in any capacity with respect to any employee benefit plan of the Company,
against all expense, liability and loss (including, but not limited to,
attorneys' fees, judgments, fines, ERISA excise taxes or penalties and amounts
paid in settlement) reasonably incurred or suffered by any such person in
connection with, or arising out of, any action, suit or proceeding, whether
civil, criminal, administrative, investigative or otherwise in which they may be
involved by reason of being or having been such a director or officer or as a
result of service with respect to any such employee benefit plan. Section 67 of
the Massachusetts Business Corporation Law authorizes a corporation to indemnify
its directors, officers, employees and other agents unless such person shall
have been adjudicated in any proceeding not to have acted in good faith in the
reasonable belief that such action was in the best interest of the corporation
or, to the extent such matter related to service with respect to an employee
benefit plan, in the best interests of the participants or beneficiaries of such
employee benefit plan.

         The effect of these provisions would be to permit indemnification by
the Company for, among other liabilities, liabilities arising out of the
Securities Act of 1933, as amended.

         Section 67 of the Massachusetts Business Corporation Law also affords a
Massachusetts corporation the power to obtain insurance on behalf of its
directors and officers against liabilities incurred by them in those capacities.
The Company has procured a directors' and officers' liability and company
reimbursement liability insurance policy that (i) insures directors and officers
of the Company against losses (above a deductible amount) arising from certain
claims made against them by reason of certain acts done or attempted by such
directors or officers and (ii) insures the Company against losses (above a
deductible amount) arising from any such claims, but only if the Company is
required or permitted to indemnify such directors or officers for such losses
under statutory or common law or under provisions of the Company's Amended and
Restated Articles of Organization or Restated By-Laws.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

ITEM 8.  EXHIBITS.

4.1      Amended and Restated Articles of Organization of the Company (filed
         as Exhibit 3.2 to the Company's registration statement on Form S-1,
         File No. 333-46941, and incorporated herein by reference).

                                      II-2
5

4.2      Amended and Restated By-Laws of the Company (filed as Exhibit 3.4
         to the Company's registration statement on Form S-1, File No.
         333-46941, and incorporated herein by reference).

4.3      Charles River Associates Incorporated 1998 Incentive and Nonqualified
         Stock Option Plan (filed as Exhibit 10.1 to the Company's registration
         statement on Form S-1, File No. 333-46941, and incorporated herein by
         reference).

5.1      Opinion of Foley, Hoag & Eliot LLP.

23.1     Consent of Ernst & Young LLP, Independent Auditors.

23.2     Consent of Foley, Hoag & Eliot LLP (included in Exhibit 5.1).

24.1     Power of Attorney (contained on the signature page).

ITEM 9.  UNDERTAKINGS.

         1. The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

         2. The undersigned registrant hereby undertakes:

              (a) To file, during any period in which offers or sales are
being made, a post-effective amendment to this registration statement:

                (i) To include any  prospectus  required by Section  10(a)(3) 
              of the Securities Act of 1933;

                (ii) To reflect in the prospectus any facts or events
              arising after the effective date of the registration statement
              (or the most recent post-effective amendment thereof) which,
              individually or in the aggregate, represent a fundamental
              change in the information set forth in the registration
              statement. Notwithstanding the foregoing, any increase or
              decrease in volume of securities offered (if the total dollar
              value of securities offered would not exceed that which was
              registered) and any deviation from the low or high end of the
              estimated maximum offering range may be reflected in the form
              of prospectus filed with the Commission pursuant to Rule
              424(b) if, in the aggregate, the changes in volume and price
              represent no more than 20 percent change in the maximum
              aggregate offering price set forth in the "Calculation of
              Registration Fee" table in the effective registration
              statement.

                                      II-3
6

                (iii) To include any material information with
              respect to the plan of distribution not previously disclosed
              in the Registration Statement or any material change to such
              information in the Registration Statement;

provided, however, that paragraphs 2 (a)(1)(i) and 2 (a)(1)(ii) do not apply if
the information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed with or furnished to the
Commission by the registrant pursuant to Section 13 or 15(d) of the Securities
Exchange Act of 1934 that are incorporated by reference herein.

              (b) That, for the purpose of determining any liability under
the Securities Act of 1933, each such post-effective amendment shall be deemed
to be a new registration statement relating to the securities offered therein,
and the offering of such securities at that time shall be deemed to be the
initial bona fide offering thereof.

              (c) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

         3.   Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the registrant pursuant to the foregoing provisions, or otherwise,
the registrant has been advised that in the opinion of the Securities and
Exchange Commission such indemnification is against public policy as expressed
in the Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
registrant of expenses incurred or paid by a director, officer or controlling
person of the registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Act and will
be governed by the final adjudication of such issue.

                                      II-4
7

                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the city of Boston, Commonwealth of Massachusetts, on this 15th
day of September, 1998.

                                 CHARLES RIVER ASSOCIATES INCORPORATED

                                 By:/s/ JAMES C. BURROWS
                                    --------------------
                                        James C. Burrows
                                        President

                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS that each individual whose signature
appears below constitutes and appoints James C. Burrows, Laurel E. Morrison and
Firoze E. Katrak, and each of them, his true and lawful attorneys-in-fact and
agents with full power of substitution, for him and in his name, place and
stead, in any and all capacities, to sign any and all amendments (including
post-effective amendments) to this registration statement, and to file the same,
with all exhibits thereto, and all documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorneys-in-fact and
agents, and each of them, full power and authority to do and perform each and
every act and thing which they, or any of them, may deem necessary or advisable
to be done in connection with this registration statement, as fully to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorneys-in-fact and agents or any of them, or any
substitute or substitutes for any or all of them, may lawfully do or cause to be
done by virtue hereof.

         Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the dates indicated.

Signature                    Title                           Date
----------                   -----                           ----

/s/ FRANKLIN  M.FISHER       Chairman of the Board           September 15, 1998
----------------------                                              
    Franklin M. Fisher

/s/ JAMES C. BURROWS         President, Cheif Executive      September 15, 1998
--------------------         Officer and Director                    
    James C. Burrows         (principal executive officer)  

                                      II-5
8

 Signature                                  Title                     Date
 --------                                   -----                     ----

/s/ LAUREL E. MORRISON         Chief Financial Officer,       September 15, 1998
----------------------         Vice President, Finance and 
    Laurel E. Morris           Administration,and Treasurer                     
                               (principal financial and
                               accounting officer

/s/ FIROZE E. KATRAK           Vice President and Director    September 15, 1998
--------------------
    Firoze E. Katrak

/s/ WILLIAM B. BURNETT         Vice President and Director    September 15, 1998
----------------------
    William B. Burnett

/s/ CARL KAYSEN                Director                       September 15, 1998
---------------                                                                
    Carl Kaysen

/s/ ROWLAND T. MORIARTY        Director                       September 15, 1998
-----------------------                                           
    Rowland T. Moriarty

                                      II-6
9

                                  EXHIBIT INDEX
                         
Exhibit
  No.             Description

4.1               Amended and Restated Articles of Organization of the
                  Company (filed as Exhibit 3.2 to the Company's registration
                  statement on Form S-1, File No. 333-46941, and incorporated
                  herein by reference).

4.2               Amended and Restated By-Laws of the Company (filed as
                  Exhibit 3.4 to the Company's registration statement on Form
                  S-1, File No. 333-46941, and incorporated herein by
                  reference).

4.3               Charles River Associates Incorporated 1998 Incentive and
                  Nonqualified Stock Option Plan (filed as Exhibit 10.1 to the
                  Company's registration statement on Form S-1, File No.
                  333-46941, and incorporated herein by reference).

5.1               Opinion of Foley, Hoag & Eliot LLP.

23.1              Consent of Ernst & Young LLP, independent auditors.

23.2              Consent of Foley, Hoag & Eliot LLP (included in Exhibit 5.1).

24.1              Power of Attorney (contained on the signature page).