content: <PAGE>   1
                                                             Registration No. 333-
  
  ================================================================================
  
                         SECURITIES AND EXCHANGE COMMISSION
  
                               WASHINGTON, D.C. 20549
  
                                      FORM S-8
  
  --------------------------------------------------------------------------------
  
                               REGISTRATION STATEMENT
  
                                        UNDER
  
                             THE SECURITIES ACT OF 1933
  
                        -------------------------------------
  
                                 ALLAIRE CORPORATION
               (Exact Name of Registrant as Specified in Its Charter)
  
                 DELAWARE                              41-1830792
      (State or Other Jurisdiction of                (I.R.S. Employer
       Incorporation or Organization)               Identification No.)
  
                                 ONE ALEWIFE CENTER
  
                           CAMBRIDGE, MASSACHUSETTS 02140
  
                                   (617) 761-2000
  
            (address, including zip code, and telephone number, including
               area code, of registrants principal executive offices)
  
                    ALLAIRE CORPORATION 1998 STOCK INCENTIVE PLAN
                              (Full Title of the Plan)
  
                                   DAVID J. ORFAO
  
                        PRESIDENT AND CHIEF EXECUTIVE OFFICER
  
                                 ALLAIRE CORPORATION
  
                                 ONE ALEWIFE CENTER
  
                           CAMBRIDGE, MASSACHUSETTS 02140
  
                       (Name and Address of Agent for Service)
                                   (617) 761-2000
  
            (Telephone Number, Including Area Code, of Agent For Service)
  
                                   With copies to:
  
                              Robert L. Birnbaum, Esq.
                                William R. Kolb, Esq.
                               Foley, Hoag & Eliot LLP
                               One Post Office Square
                             Boston, Massachusetts 02109
                                   (617) 832-1000
  
  
                           CALCULATION OF REGISTRATION FEE
  <TABLE>
  <CAPTION>
  
  ===================================================================================================================
                                                                                    Proposed
                                                                  Proposed           Maximum               Amount of
         Title of Securities                Amount          Maximum Offering        Aggregate            Registration
          to be Registered             to be Registered    Price Per Share(1)    Offering Price(1)            Fee
  ===================================================================================================================
  <S>                                  <C>                       <C>                <C>                   <C>
     Common Stock, $.01 par value      5,000,000 shares          $51.50             257,500,000             $67,980
  ===================================================================================================================
  
  </TABLE>
  
  (1)      Calculated in accordance with Rules 457(h)(1) and 457(c) under the
           Securities Act of 1933, based on the average high and low sale prices
           of Allaire's common stock as reported on the Nasdaq National Market on
           May 3, 2000.
  
  ================================================================================
  
  
  <PAGE>   2
  
           This Registration Statement covers 5,000,000 shares of our common
  stock, $.01 par value per share, issuable pursuant to the Allaire Corporation
  1998 Stock Incentive Plan, as amended as of March 13, 2000. These shares are in
  addition to the 3,800,000 shares of common stock registered pursuant to
  Allaire's Registration Statement on Form S-8, File No. 333-76855, filed with the
  Securities and Exchange Commission on April 23, 1999.
  
           The contents of Allaire's Registration Statement on Form S-8, File No.
  333-76855, as filed with the Securities and Exchange Commission on April 23,
  1999, are incorporated herein by reference.
  
  
  <PAGE>   3
  
                                       PART II
  
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  ITEM 8.  EXHIBITS.
  
           Exhibit
           NO.         DESCRIPTION
           -------     -----------
  
            4.1*       Amended  and  Restated  Certificate  of  Incorporation  of
                       Allaire Corporation
  
            4.2**      Certificate   of   Amendment   of  Amended  and   Restated
                       Certificate of Incorporation of Allaire Corporation
  
            4.3*       Amended and Restated By-Laws of Allaire Corporation
  
            4.4**      Allaire Corporation 1998 Stock Incentive Plan, as amended
  
            5.1        Opinion of Foley, Hoag & Eliot LLP
  
           23.1        Consent of PricewaterhouseCoopers LLP
  
           23.2        Consent of Foley,  Hoag & Eliot LLP  (included  in Exhibit
                        5.1)
  
  ------------
  
  *        Incorporated by reference to Allaire's  Registration  Statement on Form
           S-1 (File No. 333-63689) in the form in which it was declared effective
           by the Securities and Exchange Commission.
  
  **       Incorporated  by reference to Allaire's  Annual Report on Form 10-K for
           the year ended  December 31,  1999,  as filed with the  Securities  and
           Exchange Commission on March 30, 2000.
  
  
  
  <PAGE>   4
  
  
                                     SIGNATURES
  
           Pursuant to the requirements of the Securities Act of 1933, as amended,
  the Registrant has duly caused this Registration Statement to be signed on its
  behalf by the undersigned, thereunto duly authorized, in the City of Cambridge,
  Massachusetts on the 8th day of May, 2000.
  
                                        ALLAIRE CORPORATION
  
                                        By: /s/ David J. Orfao
                                            -------------------------
                                            David J. Orfao
                                            President and Chief Executive Officer
  
  <PAGE>   5
  
                                  POWER OF ATTORNEY
  
           KNOW ALL BY THESE PRESENTS that each individual whose signature appears
  below hereby constitutes and appoints David J. Orfao and David A. Gerth, 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, as amended,
  this Registration Statement has been signed by the following persons in the
  capacities and on the dates indicated.
  
  <TABLE>
  <CAPTION>
  
  SIGNATURE                                   TITLE                                          DATE
  ---------                                   -----                                          ----
  
  <S>                                         <C>                                            <C>
  /s/ Joseph J. Allaire                       Chairman of the Board of Directors
  ------------------------------------        and Executive Vice President,
      Joseph J. Allaire                       Products                                       May 8, 2000
  
  
  /s/ David J. Orfao                          President, Chief Executive Officer
  ------------------------------------        and Director (principal executive officer)     May 8, 2000
      David J. Orfao
  
  
  /s/ David A. Gerth                          Vice President, Finance and Operations,
  ------------------------------------        Treasurer and Chief Financial Officer
      David A. Gerth                          (principal financial and accounting officer)   May 8, 2000
  
  
  
  /S/ Jonathan A. Flint                       Director                                       May 8, 2000
  ------------------------------------
      Jonathan A. Flint
  
  
  
  /s/ John J. Gannon                          Director                                       May 8, 2000
  ------------------------------------
      John J. Gannon
  
  
  
  /s/ Thomas A. Herring                       Director                                       May 8, 2000
  ------------------------------------
      Thomas A. Herring
  
  
  
  /S/ Ronald G. Ward                          Director                                       May 8, 2000
  ------------------------------------
      Ronald G. Ward
  
  
  
  /s/ W. Frank King                           Director                                       May 8, 2000
  ------------------------------------
      William Frank King III
  
  </TABLE>
  
  
  <PAGE>   6
  
  
                                    EXHIBIT INDEX
                                    -------------
  
         EXHIBIT
         NO.            DESCRIPTION
         -------        -----------
  
           4.1*         Amended  and  Restated  Certificate  of  Incorporation  of
                        Allaire Corporation
  
           4.2**        Certificate   of   Amendment   of  Amended  and   Restated
                        Certificate of Incorporation of Allaire Corporation
  
           4.3*         Amended and Restated By-Laws of Allaire Corporation
  
           4.4**        Allaire Corporation 1998 Stock Incentive Plan, as amended
  
           5.1          Opinion of Foley, Hoag & Eliot LLP
  
          23.1          Consent of PricewaterhouseCoopers LLP
  
          23.2          Consent of Foley,  Hoag & Eliot LLP  (included  in Exhibit
                        5.1)
  
  ------------
  
  *       Incorporated by reference to Allaire's  Registration  Statement on Form
          S-1 (File No. 333-63689) in the form in which it was declared effective
          by the Securities and Exchange Commission.
  
  **      Incorporated  by reference to Allaire's  Annual Report on Form 10-K for
          the year ended  December 31,  1999,  as filed with the  Securities  and
          Exchange Commission on March 30, 2000.
metadata_documents: [{"type": "S-8", "sequence": "1", "description": "ALLAIRE CORPORATION", "secsgml_size_bytes": 10786}]
metadata_filer: {"company-data": {"conformed-name": "ALLAIRE CORP", "cik": "0001016139", "assigned-sic": "7372", "irs-number": "411812820", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-36532", "film-number": "622012"}, "business-address": {"street1": "ONE ALEWIFE CENTER 3RD FLOOR", "street2": "SUITE 552", "city": "CAMBRIDGE", "state": "MA", "zip": "02140", "phone": "6177612000"}, "mail-address": {"street1": "FOLEY HOAG & ELIOT LLP", "street2": "ONE POST OFFICE SQUARE", "city": "BOSTON", "state": "MA", "zip": "02109"}}
text: 1
                                                             Registration No. 333-
  
  ================================================================================
  
                         SECURITIES AND EXCHANGE COMMISSION
  
                               WASHINGTON, D.C. 20549
  
                                      FORM S-8
  
  --------------------------------------------------------------------------------
  
                               REGISTRATION STATEMENT
  
                                        UNDER
  
                             THE SECURITIES ACT OF 1933
  
                        -------------------------------------
  
                                 ALLAIRE CORPORATION
               (Exact Name of Registrant as Specified in Its Charter)
  
                 DELAWARE                              41-1830792
      (State or Other Jurisdiction of                (I.R.S. Employer
       Incorporation or Organization)               Identification No.)
  
                                 ONE ALEWIFE CENTER
  
                           CAMBRIDGE, MASSACHUSETTS 02140
  
                                   (617) 761-2000
  
            (address, including zip code, and telephone number, including
               area code, of registrants principal executive offices)
  
                    ALLAIRE CORPORATION 1998 STOCK INCENTIVE PLAN
                              (Full Title of the Plan)
  
                                   DAVID J. ORFAO
  
                        PRESIDENT AND CHIEF EXECUTIVE OFFICER
  
                                 ALLAIRE CORPORATION
  
                                 ONE ALEWIFE CENTER
  
                           CAMBRIDGE, MASSACHUSETTS 02140
  
                       (Name and Address of Agent for Service)
                                   (617) 761-2000
  
            (Telephone Number, Including Area Code, of Agent For Service)
  
                                   With copies to:
  
                              Robert L. Birnbaum, Esq.
                                William R. Kolb, Esq.
                               Foley, Hoag & Eliot LLP
                               One Post Office Square
                             Boston, Massachusetts 02109
                                   (617) 832-1000
  
                           CALCULATION OF REGISTRATION FEE
  ===================================================================================================================
                                                                                    Proposed
                                                                  Proposed           Maximum               Amount of
         Title of Securities                Amount          Maximum Offering        Aggregate            Registration
          to be Registered             to be Registered    Price Per Share(1)    Offering Price(1)            Fee
  ===================================================================================================================
  Common Stock, $.01 par value      5,000,000 shares          $51.50             257,500,000             $67,980
  ===================================================================================================================
  (1)      Calculated in accordance with Rules 457(h)(1) and 457(c) under the
           Securities Act of 1933, based on the average high and low sale prices
           of Allaire's common stock as reported on the Nasdaq National Market on
           May 3, 2000.
  
  ================================================================================
  2
  
           This Registration Statement covers 5,000,000 shares of our common
  stock, $.01 par value per share, issuable pursuant to the Allaire Corporation
  1998 Stock Incentive Plan, as amended as of March 13, 2000. These shares are in
  addition to the 3,800,000 shares of common stock registered pursuant to
  Allaire's Registration Statement on Form S-8, File No. 333-76855, filed with the
  Securities and Exchange Commission on April 23, 1999.
  
           The contents of Allaire's Registration Statement on Form S-8, File No.
  333-76855, as filed with the Securities and Exchange Commission on April 23,
  1999, are incorporated herein by reference.
  3
  
                                       PART II
  
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  ITEM 8.  EXHIBITS.
  
           Exhibit
           NO.         DESCRIPTION
           -------     -----------
  
            4.1*       Amended  and  Restated  Certificate  of  Incorporation  of
                       Allaire Corporation
  
            4.2**      Certificate   of   Amendment   of  Amended  and   Restated
                       Certificate of Incorporation of Allaire Corporation
  
            4.3*       Amended and Restated By-Laws of Allaire Corporation
  
            4.4**      Allaire Corporation 1998 Stock Incentive Plan, as amended
  
            5.1        Opinion of Foley, Hoag & Eliot LLP
  
           23.1        Consent of PricewaterhouseCoopers LLP
  
           23.2        Consent of Foley,  Hoag & Eliot LLP  (included  in Exhibit
                        5.1)
  
  ------------
  
  *        Incorporated by reference to Allaire's  Registration  Statement on Form
           S-1 (File No. 333-63689) in the form in which it was declared effective
           by the Securities and Exchange Commission.
  
  **       Incorporated  by reference to Allaire's  Annual Report on Form 10-K for
           the year ended  December 31,  1999,  as filed with the  Securities  and
           Exchange Commission on March 30, 2000.
  4
  
                                     SIGNATURES
  
           Pursuant to the requirements of the Securities Act of 1933, as amended,
  the Registrant has duly caused this Registration Statement to be signed on its
  behalf by the undersigned, thereunto duly authorized, in the City of Cambridge,
  Massachusetts on the 8th day of May, 2000.
  
                                        ALLAIRE CORPORATION
  
                                        By: /s/ David J. Orfao
                                            -------------------------
                                            David J. Orfao
                                            President and Chief Executive Officer
  5
  
                                  POWER OF ATTORNEY
  
           KNOW ALL BY THESE PRESENTS that each individual whose signature appears
  below hereby constitutes and appoints David J. Orfao and David A. Gerth, 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, as amended,
  this Registration Statement has been signed by the following persons in the
  capacities and on the dates indicated.
  SIGNATURE                                   TITLE                                          DATE
  ---------                                   -----                                          ----
  /s/ Joseph J. Allaire                       Chairman of the Board of Directors
  ------------------------------------        and Executive Vice President,
      Joseph J. Allaire                       Products                                       May 8, 2000
  
  /s/ David J. Orfao                          President, Chief Executive Officer
  ------------------------------------        and Director (principal executive officer)     May 8, 2000
      David J. Orfao
  
  /s/ David A. Gerth                          Vice President, Finance and Operations,
  ------------------------------------        Treasurer and Chief Financial Officer
      David A. Gerth                          (principal financial and accounting officer)   May 8, 2000
  
  /S/ Jonathan A. Flint                       Director                                       May 8, 2000
  ------------------------------------
      Jonathan A. Flint
  
  /s/ John J. Gannon                          Director                                       May 8, 2000
  ------------------------------------
      John J. Gannon
  
  /s/ Thomas A. Herring                       Director                                       May 8, 2000
  ------------------------------------
      Thomas A. Herring
  
  /S/ Ronald G. Ward                          Director                                       May 8, 2000
  ------------------------------------
      Ronald G. Ward
  
  /s/ W. Frank King                           Director                                       May 8, 2000
  ------------------------------------
      William Frank King III
  6
  
                                    EXHIBIT INDEX
                                    -------------
  
         EXHIBIT
         NO.            DESCRIPTION
         -------        -----------
  
           4.1*         Amended  and  Restated  Certificate  of  Incorporation  of
                        Allaire Corporation
  
           4.2**        Certificate   of   Amendment   of  Amended  and   Restated
                        Certificate of Incorporation of Allaire Corporation
  
           4.3*         Amended and Restated By-Laws of Allaire Corporation
  
           4.4**        Allaire Corporation 1998 Stock Incentive Plan, as amended
  
           5.1          Opinion of Foley, Hoag & Eliot LLP
  
          23.1          Consent of PricewaterhouseCoopers LLP
  
          23.2          Consent of Foley,  Hoag & Eliot LLP  (included  in Exhibit
                        5.1)
  
  ------------
  
  *       Incorporated by reference to Allaire's  Registration  Statement on Form
          S-1 (File No. 333-63689) in the form in which it was declared effective
          by the Securities and Exchange Commission.
  
  **      Incorporated  by reference to Allaire's  Annual Report on Form 10-K for
          the year ended  December 31,  1999,  as filed with the  Securities  and
          Exchange Commission on March 30, 2000.