content: <PAGE>   1
  
  
      As filed with the Securities and Exchange Commission on November 15, 1996
                                                      Registration No. 333-______
  
  ================================================================================
                         SECURITIES AND EXCHANGE COMMISSION
                               Washington, D.C. 20549
  
                             --------------------------
                                      FORM S-8
                               REGISTRATION STATEMENT
                                        under
                             THE SECURITIES ACT OF 1933
  
                          PAREXEL International Corporation
               (Exact name of registrant as specified in its charter)
  
  <TABLE>
  <S>                                                                         <C>
                           Massachusetts                                                   04-2776269
  (State or other jurisdiction of incorporation or organization)              (I.R.S. Employer Identification No.)
  </TABLE>
  
                         195 West Street, Waltham, MA 02154
                 (Address of principal executive offices) (Zip Code)
  
                                --------------------
                          PAREXEL INTERNATIONAL CORPORATION
                                   1995 STOCK PLAN
                              (Full title of the plan)
  
                               Josef H. von Rickenbach
                   President, Chief Executive Officer and Chairman
                          PAREXEL International Corporation
                                   195 West Street
                            Waltham, Massachusetts 02154
                       (Name and address of agent for service)
  
                                   (617) 487-9900
            (Telephone number, including area code of agent for service)
  
                                --------------------
                                     Copies to:
                               William J. Schnoor, Jr.
                                  Heather M. Stone
                           Testa, Hurwitz & Thibeault, LLP
                                  High Street Tower
                                   125 High Street
                                  Boston, MA 02110
                                   (617) 248-7000
  
                                --------------------
  <TABLE>
                                            Calculation Of Registration Fee
  <CAPTION>
  
  ===================================================================================================================
   Title of Securities     Amount to be        Proposed maximum           Proposed Maximum               Amount of
    to be registered        registered     offering price per share   aggregate offering price       registration fee
  -------------------------------------------------------------------------------------------------------------------
  <C>                     <C>                       <C>                      <C>                          <C>      
  Common Stock,
  $.01 par value          500,000 shares            $54.88                   $27,440,000                  $8,315.15
  
  ===================================================================================================================
  <FN>
  (1)      The price of $54.88 per share, which is the average of the bid and ask price of the Common Stock as
           reported on the Nasdaq National Market on November 8, 1996, is set forth solely for purposes of
           calculating the filing fee.
  ===================================================================================================================
  </TABLE>
  
  
  <PAGE>   2
  
  
  
          This Registration Statement registers additional securities of the same
  class as other securities for which the Registration Statement No. 33-80301 on
  Form S-8 as filed with the Securities and Exchange Commission on December 12,
  1995, relating to the PAREXEL International Corporation 1986 Employee Incentive
  Stock Option Plan, 1987 Stock Plan, 1989 Stock Plan, 1995 Stock Plan, 1995
  Employee Stock Purchase Plan and the 1995 Non-Employee Director Stock Option
  Plan is effective. Pursuant to General Instruction E, the contents of the
  above-listed Registration Statement are hereby incorporated by reference.
  
  
                                       PART II
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  Item 8.  Exhibits
           --------
  
          Exhibit No.    Description of Exhibit
          -----------    ----------------------
  
          Exhibit 5.1    Opinion of Testa, Hurwitz & Thibeault, LLP.
  
          Exhibit 23.1   Consent of Price Waterhouse LLP.
  
          Exhibit 23.2   Consent of Testa, Hurwitz & Thibeault, LLP (included in
                         Exhibit 5.1).
  
          Exhibit 24.1   Power of Attorney (included as part of the signature
                         page to this Registration Statement).
  
  
  
  
  
                                         2
  <PAGE>   3
  
  
                                     SIGNATURES
  
           Pursuant to the requirements of the Securities Act of 1933, the
  Registrant, PAREXEL International Corporation 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 Waltham, State of
  Massachusetts, on this 15th day of November, 1996.
  
                                        PAREXEL INTERNATIONAL CORPORATION
  
  
                                    By: /s/ Josef H. von Rickenbach
                                        ------------------------------------------
                                        Josef H. von Rickenbach
                                        President, Chief Executive Officer and
                                        Chairman
  
                                  POWER OF ATTORNEY
  
           KNOW ALL PERSONS BY THESE PRESENTS, that each such person whose
  signature appears below constitutes and appoints, jointly and severally, Josef
  H. von Rickenbach, William T. Sobo, Jr. and William J. Schnoor, Jr., his
  attorneys-in-fact, each with the power of substitution, for him in any and all
  capacities, to sign any amendments to this Registration Statement on Form S-8
  (including post-effective amendments), and to file the same, with all exhibits
  thereto, and other documents in connection therewith, with the Securities and
  Exchange Commission, hereby ratifying and confirming all that each of said
  attorneys-in-fact, or his substitute or substitutes, may do or cause to be done
  by virtue hereof.
  
  <TABLE>
           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.
  <CAPTION>
  
             Signature                           Title                                 Date
             ---------                           -----                                 ----
  
     <S>                                  <C>                                   <C> 
     /s/ Josef H. von Rickenbach          President, Chief Executive            November 15, 1996
     -----------------------------------  Officer and Chairman (principal
     Josef H. von Rickenbach              executive officer)
  
     /s/ William T. Sobo, Jr.             Vice President and Treasurer          November 15, 1996
     -----------------------------------  (principal financial and
     William T. Sobo, Jr.                 accounting officer)
  
     /s/ A. Dana Callow                   Director                              November 15, 1996
     -----------------------------------
     A. Dana Callow
  
     /s/ Patrick J. Fortune               Director                              November 15, 1996
     -----------------------------------
     Patrick J. Fortune
  
     /s/ Werner M. Herrmann               Director                              November 15, 1996
     -----------------------------------
     Werner M. Herrmann
  
     /s/ Peter Barton Hutt                Director                              November 15, 1996
     -----------------------------------
     Peter Barton Hutt
  
     /s/ James Saalfield                  Director                              November 15, 1996
     -----------------------------------
     James Saalfield
  </TABLE>
  
  
                                         3
  <PAGE>   4
  
  
                                  INDEX TO EXHIBITS
  
  
  EXHIBIT NO.                        DESCRIPTION                              PAGE
  -----------                        -----------                              ----
  
  Exhibit 5.1       Opinion of Testa, Hurwitz & Thibeault, LLP.
  
  Exhibit 23.1      Consent of Price Waterhouse LLP.
  
  Exhibit 23.2      Consent of Testa, Hurwitz & Thibeault, LLP (included 
                    in Exhibit 5.1).
  
  Exhibit 24.1      Power of Attorney (included as part of the signature 
                    page to this Registration Statement).
  
  
  
                                         4
metadata_documents: [{"type": "S-8", "sequence": "1", "description": "PAREXEL INTERNATIONAL CORP. FORM S-8", "secsgml_size_bytes": 8995}]
metadata_filer: {"company-data": {"conformed-name": "PAREXEL INTERNATIONAL CORP", "cik": "0000799729", "assigned-sic": "8731", "irs-number": "042776269", "state-of-incorporation": "MA", "fiscal-year-end": "0630"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-16205", "film-number": "96667429"}, "business-address": {"street1": "195 WEST ST", "city": "WALTHAM", "state": "MA", "zip": "02154", "phone": "6174879900"}, "mail-address": {"street1": "195 WEST ST", "city": "WALTHAM", "state": "MA", "zip": "02154"}}
text: 1
  
      As filed with the Securities and Exchange Commission on November 15, 1996
                                                      Registration No. 333-______
  
  ================================================================================
                         SECURITIES AND EXCHANGE COMMISSION
                               Washington, D.C. 20549
  
                             --------------------------
                                      FORM S-8
                               REGISTRATION STATEMENT
                                        under
                             THE SECURITIES ACT OF 1933
  
                          PAREXEL International Corporation
               (Exact name of registrant as specified in its charter)
  Massachusetts                                                   04-2776269
  (State or other jurisdiction of incorporation or organization)              (I.R.S. Employer Identification No.)
  195 West Street, Waltham, MA 02154
                 (Address of principal executive offices) (Zip Code)
  
                                --------------------
                          PAREXEL INTERNATIONAL CORPORATION
                                   1995 STOCK PLAN
                              (Full title of the plan)
  
                               Josef H. von Rickenbach
                   President, Chief Executive Officer and Chairman
                          PAREXEL International Corporation
                                   195 West Street
                            Waltham, Massachusetts 02154
                       (Name and address of agent for service)
  
                                   (617) 487-9900
            (Telephone number, including area code of agent for service)
  
                                --------------------
                                     Copies to:
                               William J. Schnoor, Jr.
                                  Heather M. Stone
                           Testa, Hurwitz & Thibeault, LLP
                                  High Street Tower
                                   125 High Street
                                  Boston, MA 02110
                                   (617) 248-7000
  
                                --------------------
  
                                            Calculation Of Registration Fee
  ===================================================================================================================
   Title of Securities     Amount to be        Proposed maximum           Proposed Maximum               Amount of
    to be registered        registered     offering price per share   aggregate offering price       registration fee
  -------------------------------------------------------------------------------------------------------------------
  Common Stock,
  $.01 par value          500,000 shares            $54.88                   $27,440,000                  $8,315.15
  
  ===================================================================================================================
  (1)      The price of $54.88 per share, which is the average of the bid and ask price of the Common Stock as
           reported on the Nasdaq National Market on November 8, 1996, is set forth solely for purposes of
           calculating the filing fee.
  ===================================================================================================================
  2
  
          This Registration Statement registers additional securities of the same
  class as other securities for which the Registration Statement No. 33-80301 on
  Form S-8 as filed with the Securities and Exchange Commission on December 12,
  1995, relating to the PAREXEL International Corporation 1986 Employee Incentive
  Stock Option Plan, 1987 Stock Plan, 1989 Stock Plan, 1995 Stock Plan, 1995
  Employee Stock Purchase Plan and the 1995 Non-Employee Director Stock Option
  Plan is effective. Pursuant to General Instruction E, the contents of the
  above-listed Registration Statement are hereby incorporated by reference.
  
                                       PART II
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  Item 8.  Exhibits
           --------
  
          Exhibit No.    Description of Exhibit
          -----------    ----------------------
  
          Exhibit 5.1    Opinion of Testa, Hurwitz & Thibeault, LLP.
  
          Exhibit 23.1   Consent of Price Waterhouse LLP.
  
          Exhibit 23.2   Consent of Testa, Hurwitz & Thibeault, LLP (included in
                         Exhibit 5.1).
  
          Exhibit 24.1   Power of Attorney (included as part of the signature
                         page to this Registration Statement).
  
                                         2
  3
  
                                     SIGNATURES
  
           Pursuant to the requirements of the Securities Act of 1933, the
  Registrant, PAREXEL International Corporation 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 Waltham, State of
  Massachusetts, on this 15th day of November, 1996.
  
                                        PAREXEL INTERNATIONAL CORPORATION
  
                                    By: /s/ Josef H. von Rickenbach
                                        ------------------------------------------
                                        Josef H. von Rickenbach
                                        President, Chief Executive Officer and
                                        Chairman
  
                                  POWER OF ATTORNEY
  
           KNOW ALL PERSONS BY THESE PRESENTS, that each such person whose
  signature appears below constitutes and appoints, jointly and severally, Josef
  H. von Rickenbach, William T. Sobo, Jr. and William J. Schnoor, Jr., his
  attorneys-in-fact, each with the power of substitution, for him in any and all
  capacities, to sign any amendments to this Registration Statement on Form S-8
  (including post-effective amendments), and to file the same, with all exhibits
  thereto, and other documents in connection therewith, with the Securities and
  Exchange Commission, hereby ratifying and confirming all that each of said
  attorneys-in-fact, or his substitute or substitutes, may 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/ Josef H. von Rickenbach          President, Chief Executive            November 15, 1996
     -----------------------------------  Officer and Chairman (principal
     Josef H. von Rickenbach              executive officer)
  
     /s/ William T. Sobo, Jr.             Vice President and Treasurer          November 15, 1996
     -----------------------------------  (principal financial and
     William T. Sobo, Jr.                 accounting officer)
  
     /s/ A. Dana Callow                   Director                              November 15, 1996
     -----------------------------------
     A. Dana Callow
  
     /s/ Patrick J. Fortune               Director                              November 15, 1996
     -----------------------------------
     Patrick J. Fortune
  
     /s/ Werner M. Herrmann               Director                              November 15, 1996
     -----------------------------------
     Werner M. Herrmann
  
     /s/ Peter Barton Hutt                Director                              November 15, 1996
     -----------------------------------
     Peter Barton Hutt
  
     /s/ James Saalfield                  Director                              November 15, 1996
     -----------------------------------
     James Saalfield
  3
  4
  
                                  INDEX TO EXHIBITS
  
  EXHIBIT NO.                        DESCRIPTION                              PAGE
  -----------                        -----------                              ----
  
  Exhibit 5.1       Opinion of Testa, Hurwitz & Thibeault, LLP.
  
  Exhibit 23.1      Consent of Price Waterhouse LLP.
  
  Exhibit 23.2      Consent of Testa, Hurwitz & Thibeault, LLP (included 
                    in Exhibit 5.1).
  
  Exhibit 24.1      Power of Attorney (included as part of the signature 
                    page to this Registration Statement).
  
                                         4