Washington, DC 20549

                                  SCHEDULE 14A
                                 (Rule 14a-101)

                            SCHEDULE 14A INFORMATION

                Proxy Statement Pursuant to Section 14(a) of the
                         Securities Exchange Act of 1934

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    Rule 14a-6(e)(2))
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                                   KADANT INC.
             (Exact Name of Registrant as Specified in its Charter)

    (Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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                                   KADANT INC.

Kadant Inc.
One Acton Place, Suite 202
Acton, MA  01720

                                                                    May 17, 2006

To Stockholders of

          Supplement to Definitive Proxy Statement dated April 17, 2006

        On May 17, 2006, the Board of Directors of Kadant Inc. (the "Company")
amended the 2006 Equity Incentive Plan (the "Plan"), which is the subject of
"Proposal 2, Proposal to Approve the 2006 Equity Incentive Plan" contained in
the Company's Definitive Proxy Statement dated April 17, 2006 (the "Proxy
Statement"). The amendment reduced the number of shares authorized for issuance
under the Plan from 1,000,000 shares of common stock, $0.01 par value, to
900,000 shares. As a consequence, if the stockholders approve the Plan at the
Annual Meeting of Stockholders on May 25, 2006, the number of shares of the
Company's common stock available for issuance under the Plan will be 900,000
shares, not 1,000,000 shares as stated in Proposal 2 of the Proxy Statement.

        The amendment to the Plan, which is set forth as Appendix A in the
Proxy Statement, amends Section 4.1 "Authorized Number of Shares" to read as
        "Subject to adjustment as provided in Section 9.6, the total number of
shares of common stock of the Company, par value $0.01 per share (the "Common
Stock"), reserved and available for distribution under the Plan shall be 900,000
shares. Such shares may consist, in whole or in part, of authorized and unissued
shares or treasury shares."

        No other provisions of the Plan or the Proxy Statement were amended.

        This supplement is sent to you by order of our Board of Directors.

                                   SANDRA L. LAMBERT
                                   Vice President, General Counsel and Secretary