<PAGE>
 
   As filed with the Securities and Exchange Commission on November 25, 1998



                                                 Registration No. 333-



                      SECURITIES AND EXCHANGE COMMISSION

                            WASHINGTON, D.C.  20549
                                
                                ---------------


                                   FORM S-8

            REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933


                           Scientific-Atlanta, Inc.
            (Exact Name of Registrant as Specified in Its Charter)



         GEORGIA                                         58-0612397
(State or Other Jurisdiction of             (I.R.S. Employer Identification No.)
 Incorporation or Organization)


    ONE TECHNOLOGY PARKWAY, SOUTH                          30092-2967
         NORCROSS, GEORGIA                                 (Zip Code)
(Address of Principal Executive Offices)




                     LONG-TERM INCENTIVE PLAN, AS AMENDED
                           (Full Title of the Plan)



        James F. McDonald        Please address a copy of all communications to:
       Chief Executive Officer
       Scientific-Atlanta, Inc.                William E. Eason, Jr., Esq.
    One Technology Parkway, South                Scientific-Atlanta, Inc.
      Norcross, Georgia 30092                 One Technology Parkway, South
(Name and Address of Agent For Service)          Norcross, Georgia  30092
                                                Telephone:  (770) 903-5000

                (770) 903-5000
(Telephone Number, Including Area Code, of Agent for Service)



                        CALCULATION OF REGISTRATION FEE

===============================================================================
                                Proposed        Proposed
 Title of                       Maximum         Maximum
Securities         Amount       Offering       Aggregate       Amount of
  to be            to be         Price          Offering      Registration
Registered       Registered   Per Share(1)       Price           Fee
===============================================================================
Common
Stock, Par
Value $0.50      3,000,000     $16.8125       $50,437,500     $14,022.00
Per Share        shares
===============================================================================

(1)   Calculated pursuant to Rules 457(c) and 457(h)(1), based on the average of
      the high and low sale prices ($16.8125 per share) of the Common Stock of
      the Registrant on the New York Stock Exchange on November 19, 1998.
<PAGE>
 
                     STATEMENT UNDER GENERAL INSTRUCTION E

                     REGISTRATION OF ADDITIONAL SECURITIES



        This Registration Statement pertains to additional shares of
Registrant's common stock that may be issued pursuant to the Long-Term Incentive
Plan, as amended effective November 11, 1998 (the "Amended Plan"). The Amended
Plan was effective November 11, 1998, and unless otherwise noted herein, the
contents of Registrant's Form S-8 Registration Statement (File No. 33-56449)
relating to Registrant's Long-Term Incentive Plan prior to its amendment are
incorporated by reference into this Registration Statement on Form S-8.


                                    PART II

              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


ITEM 8. EXHIBITS

       The exhibits filed as part of this Registration Statement are as follows:



Exhibit Number         Description of Exhibit
--------------         ----------------------

    4             Long-Term Incentive Plan, As Amended Effective November 11,
                  1998

    5             Opinion of William E. Eason, Jr., General Counsel of
                  Registrant, as to the legality of the securities being
                  registered

   23.1           Consent of Arthur Andersen LLP

   23.2           Consent of William E. Eason, Jr. (included in the opinion
                  filed as Exhibit 5)

   24             Power of Attorney authorizing James F. McDonald and Wallace G.
                  Haislip to sign amendments to this Registration Statement on
                  behalf of officers and directors of the Registrant (contained
                  on Signature Page of Registration Statement)
<PAGE>
 
                                  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 Gwinnett County, State of Georgia, on this 25th day of November,
1998.


                                 SCIENTIFIC-ATLANTA, INC.


                                 By:  /s/ James F. McDonald
                                      ---------------------
                                      JAMES F. MCDONALD, PRESIDENT AND
                                      CHIEF EXECUTIVE OFFICER



                               POWER OF ATTORNEY
                               -----------------



        KNOW ALL MEN BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints James F. McDonald and Wallace G. Haislip,
jointly and severally, his or her attorneys-in-fact, each with power of
substitution for him or her in any and all capacities, to sign any amendments to
this Registration Statement, and to file the same, with the 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 below by the following persons in the
capacities and on the date indicated.



/s/ James F. McDonald                             November 25, 1998
---------------------                             -----------------
JAMES F. MCDONALD, PRESIDENT AND CHIEF            Date
EXECUTIVE OFFICER AND DIRECTOR
(PRINCIPAL EXECUTIVE OFFICER)



/s/ Wallace G. Haislip                            November 25, 1998
----------------------                            -------------------
WALLACE G. HAISLIP, SENIOR VICE PRESIDENT-        Date
FINANCE, CHIEF FINANCIAL OFFICER AND TREASURER
(PRINCIPAL FINANCIAL OFFICER)



/s/ Julian W. Eidson                              November 25, 1998
--------------------                              -----------------
JULIAN W. EIDSON                                  Date
VICE PRESIDENT AND CONTROLLER
(PRINCIPAL ACCOUNTING OFFICER)



                      [Signatures continued on next page]
<PAGE>
 
                  [Signatures continued from preceding page]



/s/ Marion H. Antonini                            November 25, 1998
-----------------------                           -----------------
MARION H. ANTONINI                                Date
DIRECTOR



/s/ David W. Dorman                               November 25, 1998
-----------------------                           -----------------
DAVID W. DORMAN                                   Date
DIRECTOR



/s/ William E. Kassling                           November 25, 1998
-----------------------                           -----------------
WILLIAM E. KASSLING                               Date
DIRECTOR



/s/ Mylle Bell Mangum                             November 25, 1998
-----------------------                           -----------------
MYLLE BELL MANGUM                                 Date
DIRECTOR



/s/ David J. McLaughlin                           November 25, 1998
-----------------------                           -----------------
DAVID J. MCLAUGHLIN                               Date
DIRECTOR



/s/ James V. Napier                               November 25, 1998
-----------------------                           -----------------
JAMES V. NAPIER                                   Date
DIRECTOR



/s/ Sam Nunn                                      November 25, 1998
-----------------------                           -----------------
SAM NUNN                                          Date
DIRECTOR
<PAGE>
 
                                 EXHIBIT INDEX



Exhibits
--------


 4      Long-Term Incentive Plan, As Amended Effective November 11, 1998

 5      Opinion of William E. Eason, Jr., General Counsel of Registrant, as to
        the legality of the securities being registered

23.1    Consent of Arthur Andersen LLP

23.2    Consent of William E. Eason, Jr. (included in the opinion filed as
        Exhibit 5)

24      Power of Attorney authorizing James F. McDonald and Wallace G. Haislip
        to sign amendments to this Registration Statement on behalf of officers
        and directors of the Registrant (contained on Signature Page of
        Registration Statement)
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 9053}]
{"company-data": {"conformed-name": "SCIENTIFIC ATLANTA INC", "cik": "0000087777", "assigned-sic": "3663", "irs-number": "580612397", "state-of-incorporation": "GA", "fiscal-year-end": "0630"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-67931", "film-number": "98759090"}, "business-address": {"street1": "ONE TECHNOLOGY PKWY S", "city": "NORCROSS", "state": "GA", "zip": "30092-2967", "phone": "7709035000"}, "mail-address": {"street1": "ONE TECHNOLOGY PKWY S", "city": "NORCROSS", "state": "GA", "zip": "30092-2967"}, "former-company": {"former-conformed-name": "SCIENTIFIC ASSOCIATES INC", "date-changed": "19671024"}}
As filed with the Securities and Exchange Commission on November 25, 1998

                                                 Registration No. 333-

                      SECURITIES AND EXCHANGE COMMISSION

                            WASHINGTON, D.C.  20549
                                
                                ---------------

                                   FORM S-8

            REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                           Scientific-Atlanta, Inc.
            (Exact Name of Registrant as Specified in Its Charter)

         GEORGIA                                         58-0612397
(State or Other Jurisdiction of             (I.R.S. Employer Identification No.)
 Incorporation or Organization)

    ONE TECHNOLOGY PARKWAY, SOUTH                          30092-2967
         NORCROSS, GEORGIA                                 (Zip Code)
(Address of Principal Executive Offices)

                     LONG-TERM INCENTIVE PLAN, AS AMENDED
                           (Full Title of the Plan)

        James F. McDonald        Please address a copy of all communications to:
       Chief Executive Officer
       Scientific-Atlanta, Inc.                William E. Eason, Jr., Esq.
    One Technology Parkway, South                Scientific-Atlanta, Inc.
      Norcross, Georgia 30092                 One Technology Parkway, South
(Name and Address of Agent For Service)          Norcross, Georgia  30092
                                                Telephone:  (770) 903-5000

                (770) 903-5000
(Telephone Number, Including Area Code, of Agent for Service)

                        CALCULATION OF REGISTRATION FEE

===============================================================================
                                Proposed        Proposed
 Title of                       Maximum         Maximum
Securities         Amount       Offering       Aggregate       Amount of
  to be            to be         Price          Offering      Registration
Registered       Registered   Per Share(1)       Price           Fee
===============================================================================
Common
Stock, Par
Value $0.50      3,000,000     $16.8125       $50,437,500     $14,022.00
Per Share        shares
===============================================================================

(1)   Calculated pursuant to Rules 457(c) and 457(h)(1), based on the average of
      the high and low sale prices ($16.8125 per share) of the Common Stock of
      the Registrant on the New York Stock Exchange on November 19, 1998.
STATEMENT UNDER GENERAL INSTRUCTION E

                     REGISTRATION OF ADDITIONAL SECURITIES

        This Registration Statement pertains to additional shares of
Registrant's common stock that may be issued pursuant to the Long-Term Incentive
Plan, as amended effective November 11, 1998 (the "Amended Plan"). The Amended
Plan was effective November 11, 1998, and unless otherwise noted herein, the
contents of Registrant's Form S-8 Registration Statement (File No. 33-56449)
relating to Registrant's Long-Term Incentive Plan prior to its amendment are
incorporated by reference into this Registration Statement on Form S-8.

                                    PART II

              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 8. EXHIBITS

       The exhibits filed as part of this Registration Statement are as follows:

Exhibit Number         Description of Exhibit
--------------         ----------------------

    4             Long-Term Incentive Plan, As Amended Effective November 11,
                  1998

    5             Opinion of William E. Eason, Jr., General Counsel of
                  Registrant, as to the legality of the securities being
                  registered

   23.1           Consent of Arthur Andersen LLP

   23.2           Consent of William E. Eason, Jr. (included in the opinion
                  filed as Exhibit 5)

   24             Power of Attorney authorizing James F. McDonald and Wallace G.
                  Haislip to sign amendments to this Registration Statement on
                  behalf of officers and directors of the Registrant (contained
                  on Signature Page of Registration Statement)
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 Gwinnett County, State of Georgia, on this 25th day of November,
1998.

                                 SCIENTIFIC-ATLANTA, INC.

                                 By:  /s/ James F. McDonald
                                      ---------------------
                                      JAMES F. MCDONALD, PRESIDENT AND
                                      CHIEF EXECUTIVE OFFICER

                               POWER OF ATTORNEY
                               -----------------

        KNOW ALL MEN BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints James F. McDonald and Wallace G. Haislip,
jointly and severally, his or her attorneys-in-fact, each with power of
substitution for him or her in any and all capacities, to sign any amendments to
this Registration Statement, and to file the same, with the 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 below by the following persons in the
capacities and on the date indicated.

/s/ James F. McDonald                             November 25, 1998
---------------------                             -----------------
JAMES F. MCDONALD, PRESIDENT AND CHIEF            Date
EXECUTIVE OFFICER AND DIRECTOR
(PRINCIPAL EXECUTIVE OFFICER)

/s/ Wallace G. Haislip                            November 25, 1998
----------------------                            -------------------
WALLACE G. HAISLIP, SENIOR VICE PRESIDENT-        Date
FINANCE, CHIEF FINANCIAL OFFICER AND TREASURER
(PRINCIPAL FINANCIAL OFFICER)

/s/ Julian W. Eidson                              November 25, 1998
--------------------                              -----------------
JULIAN W. EIDSON                                  Date
VICE PRESIDENT AND CONTROLLER
(PRINCIPAL ACCOUNTING OFFICER)

                      [Signatures continued on next page]
[Signatures continued from preceding page]

/s/ Marion H. Antonini                            November 25, 1998
-----------------------                           -----------------
MARION H. ANTONINI                                Date
DIRECTOR

/s/ David W. Dorman                               November 25, 1998
-----------------------                           -----------------
DAVID W. DORMAN                                   Date
DIRECTOR

/s/ William E. Kassling                           November 25, 1998
-----------------------                           -----------------
WILLIAM E. KASSLING                               Date
DIRECTOR

/s/ Mylle Bell Mangum                             November 25, 1998
-----------------------                           -----------------
MYLLE BELL MANGUM                                 Date
DIRECTOR

/s/ David J. McLaughlin                           November 25, 1998
-----------------------                           -----------------
DAVID J. MCLAUGHLIN                               Date
DIRECTOR

/s/ James V. Napier                               November 25, 1998
-----------------------                           -----------------
JAMES V. NAPIER                                   Date
DIRECTOR

/s/ Sam Nunn                                      November 25, 1998
-----------------------                           -----------------
SAM NUNN                                          Date
DIRECTOR
EXHIBIT INDEX

Exhibits
--------

 4      Long-Term Incentive Plan, As Amended Effective November 11, 1998

 5      Opinion of William E. Eason, Jr., General Counsel of Registrant, as to
        the legality of the securities being registered

23.1    Consent of Arthur Andersen LLP

23.2    Consent of William E. Eason, Jr. (included in the opinion filed as
        Exhibit 5)

24      Power of Attorney authorizing James F. McDonald and Wallace G. Haislip
        to sign amendments to this Registration Statement on behalf of officers
        and directors of the Registrant (contained on Signature Page of
        Registration Statement)