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Commission File No.: 0-29954

FORM 6-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
 Washington DC 20549

Report of Foreign Issuer

Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

For the month of November 2002

THE THOMSON CORPORATION
(Translation of registrant's name into English)

Suite 2706, Toronto Dominion Bank Tower
P.O. Box 24, 66 Wellington St. West
Toronto-Dominion Centre
Toronto, Ontario
M5K 1A1, Canada
(Address of principal executive offices)

        Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F o    Form 40-F ý

        Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes o    No ý

        If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-.

EXHIBIT INDEX IS LOCATED AT PAGE 2 OF 36

Information furnished on this form:

        Management's Discussion and Analysis and Third Quarter Report for the Nine Months Ended September 30, 2002.


EXHIBIT

Exhibit Number
    
   Page
1.   Management's Discussion and Analysis and Third Quarter Report for the Nine Months Ended September 30, 2002   6

2.
 
Controls and Procedures
 
34

3.
 
Two Certifications Pursuant to 18 U.S.C. Section 1350, As Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
 
35

2


SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained in Exhibit number 1 constitute forward-looking statements, which are based on the Corporation's current expectations and assumptions, and are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated. Such risks and uncertainties include, among others, general business and economic conditions and competitive actions.


SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

    The Thomson Corporation
(Registrant)

Date: November 6, 2002
 
/s/  PAULA R. MONAGHAN      
Assistant Secretary


CERTIFICATION

        I, Richard J. Harrington, certify that:

1.
I have reviewed this report on Form 6-K of The Thomson Corporation;

2.
Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.
Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.
The registrant's other certifying officers and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rules 13a-14 and 15d-14 of the Securities Exchange Act of 1934) for the registrant and have:

a)
designed such disclosure controls and procedures to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b)
evaluated the effectiveness of the registrant's disclosure controls and procedures as of a date within 90 days prior to the filing date of this report (the "Evaluation Date"); and

c)
presented in this report our conclusions about the effectiveness of the disclosure controls and procedures based on our evaluation as of the Evaluation Date;
5.
The registrant's other certifying officers and I have disclosed, based on our most recent evaluation, to the registrant's auditors and the audit committee of registrant's board of directors (or persons performing the equivalent function):

a)
all significant deficiencies in the design or operation of internal controls which could adversely affect the registrant's ability to record, process, summarize and report financial data and have identified for the registrant's auditors any material weaknesses in internal controls; and

3

6.
The registrant's other certifying officers and I have indicated in this report whether or not there were significant changes in internal controls or in other factors that could significantly affect internal controls subsequent to the date of our most recent evaluation, including any corrective actions with regard to significant deficiencies and material weaknesses.

Date: November 6, 2002

    /s/  RICHARD J. HARRINGTON      
Richard J. Harrington
President and Chief Executive Officer

4


CERTIFICATION

        I, Robert D. Daleo, certify that:

1.
I have reviewed this report on Form 6-K of The Thomson Corporation;

2.
Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.
Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.
The registrant's other certifying officers and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rules 13a-14 and 15d-14 of the Securities Exchange Act of 1934) for the registrant and have:

a)
designed such disclosure controls and procedures to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b)
evaluated the effectiveness of the registrant's disclosure controls and procedures as of a date within 90 days prior to the filing date of this report (the "Evaluation Date"); and

c)
presented in this report our conclusions about the effectiveness of the disclosure controls and procedures based on our evaluation as of the Evaluation Date;
5.
The registrant's other certifying officers and I have disclosed, based on our most recent evaluation, to the registrant's auditors and the audit committee of registrant's board of directors (or persons performing the equivalent function):

a)
all significant deficiencies in the design or operation of internal controls which could adversely affect the registrant's ability to record, process, summarize and report financial data and have identified for the registrant's auditors any material weaknesses in internal controls; and

b)
any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal controls; and
6.
The registrant's other certifying officers and I have indicated in this report whether or not there were significant changes in internal controls or in other factors that could significantly affect internal controls subsequent to the date of our most recent evaluation, including any corrective actions with regard to significant deficiencies and material weaknesses.

Date: November 6, 2002

    /s/  ROBERT D. DALEO      
Robert D. Daleo
Executive Vice President and
Chief Financial Officer

5



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EXHIBIT
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
SIGNATURES
CERTIFICATION
CERTIFICATION