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Exhibit 32.1

CERTIFICATION
PURSUANT TO 18 U.S.C. SECTION 1350,
AS ADOPTED BY SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        I, René Lerer, as Chief Executive Officer of Magellan Health Services, Inc. (the "Company") certify, pursuant to 18 U.S.C. ss. 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

        (1)   the accompanying Form 10-K report for the period ending December 31, 2007 as filed with the U.S. Securities and Exchange Commission (the "Report") fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

        (2)   the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: February 29, 2007

/s/  RENÉ LERER Name: René Lerer
Title: Chief Executive Officer

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Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED BY SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002