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EXHIBIT NO. 99.10(a)
INDEPENDENT AUDITORS' CONSENT
We consent to the incorporation by reference in this Post-Effective Amendment
No. 29 to Registration No. 2-60491 of MFS Series Trust III of our reports dated
March 9, 2000, appearing in the annual reports to shareholders for the year
ended January 31, 1999, of MFS High Yield Opportunities Fund and MFS High Income
Fund, and to the references to us under the headings "Financial Highlights" in
the Prospectus and "Independent Auditors and Financial Statements" in the
Statement of Additional Information, all of which are part of such Registration
Statement.
DELOTTE & TOUCHE LLP
Deloitte & Touche LLP
Boston, Massachusetts
May 23, 2000
