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EXHIBIT NO. 99.10(b)
INDEPENDENT AUDITORS' CONSENT
We consent to the reference made to our firm under the captions "Financial
Highlights" in the Prospectus and "Independent Auditors and Financial
Statements" in the Statement of Additional Information and to the incorporation
by reference in this Post-Effective Amendment No. 29 to Registration No. 2-60491
on Form N-1A of our report dated March 8, 2000 on the financial statements and
financial highlights of MFS Municipal High Income Fund, a series of MFS Series
Trust III appearing in the Fund's 2000 Annual Report to Shareholders.
ERNST & YOUNG, LLP
Ernst & Young, LLP
Boston, Massachusetts
May 23, 2000
