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                                                                Exhibit 10(iii)b

                     THIRD AMENDMENT TO EMPLOYMENT AGREEMENT

         THIS THIRD AMENDMENT TO THE EMPLOYMENT AGREEMENT dated as of September
1, 1999, as amended July 10, 2000, and October 2, 2000, (the "AGREEMENT") by and
between Commercial Metals Company, a Delaware corporation (the "COMPANY"), and
Murray R. McClean (the "EXECUTIVE") is made this 28th day of March, 2001.

                                    RECITALS:

         WHEREAS, the Company and the Executive entered into an Employment
Agreement as of September 1, 1999, which was amended by a First Amendment dated
July 10, 2000; and a Second Amendment dated October 2, 2000; and

         WHEREAS, the Company and the Executive wish to further amend the
Agreement to provide Executive with funds for unanticipated expenses incurred by
the Executive and related to the Executive's relocation from Australia to the
United States;

         NOW THEREFORE, in consideration of the mutual covenants and agreements
contained herein, the Company and Executive agree to amend the Agreement to add
to Article I, Section 1.4 Compensation a new paragraph 1.4(k) which shall read
as follows:

(k)      Additional Loan. In addition to the mortgage relocation loan and the
         other relocation expense loan referred to Paragraph 1.4(i), the Company
         shall loan the Executive an additional Forty Thousand Dollars
         ($40,000.00) to be drawn down as requested by the Executive on or
         before April 16, 2001. This additional loan shall be evidenced by an
         appropriate promissory note providing for payment of accrued interest
         in ten equal payments of principal, each in the amount of Four Thousand
         Dollars ($4,000.00), to be deducted from Executive's net after-tax
         annual bonus payment as may be made by the Company to Executive in
         October of each year commencing in October, 2001. Should any annual
         bonus payment due Executive not equal the installment then due, the
         unpaid balance of principal only shall be added to the next year's
         installment with all the remaining unpaid principal balance and accrued
         interest due and payable on or before October 31, 2010. All accrued
         interest for each period preceding a installment payment date shall be
         paid by Executive no later than October 31 of each year either by
         deduction from Executive's net after tax annual bonus payment or
         directly by Executive if the bonus payment is not sufficient. The note
         evidencing this additional loan shall further provide that it shall be
         due and payable in full within 120 days of the termination of the
         Executive's employment with the Company for any reason. Furthermore,
         the note shall provide for interest at a rate equal to the one-year
         United States Treasury constant maturity rate for the month of July,
         2000, as published by the Federal Reserve Board of Governors plus one
         percent (1%) and shall be adjusted commencing September 1, 2001 and
         annually each September 1 thereafter to the
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         then most recently published one year constant maturity rate for the
         month of July of each succeeding year plus one percent (1%). At the
         option and expense of the Company, the Executive's obligations under
         the note may be secured by a second mortgage note on the Australian
         Property.

         Except as specifically provided herein, the Agreement is in all
respects ratified and confirmed, and all the terms, conditions and provisions
thereof shall be and remain in full force and effect for any and all purposes.
From and after the date of this Third Amendment, any and all references to the
Agreement shall refer to the Agreement as amended by the First, Second and Third
Amendments.

         IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment
to be duly executed as of the date first above written.

                                           /s/ MURRAY R. McCLEAN
                                           ------------------------------------
                                           MURRAY R. McCLEAN



                                           COMMERCIAL METALS COMPANY

                                           BY: /s/ STANLEY A. RABIN
                                               --------------------------------
                                                  STANLEY A. RABIN
                                                  Chairman, President and
                                                  Chief Executive Officer