The Library of Congress Medium of Performance Thesaurus for Music (LCMPT) has been developed jointly by the Music Library Association Cataloging and Metadata Committee (formerly the Bibliographic Control Committee) and the Library of Congress Policy and Standards Division. When work began on the music portion of the Library of Congress Genre/Form Terms for Library and Archival Materials (LCGFT), it was decided early on that medium of performance terms (i.e., the voices, instruments, and other entities needed to perform a piece of music) would be out of scope; therefore, development began on LCMPT as a separate vocabulary to house those terms.

LCMPT consists of over 800 medium of performance terms, including most of the medium terms currently in LCSH, as well as some new terms. The terminology in LCMPT is designed to be used in both authority records (as an alternative to the RDA medium of performance vocabulary) and in bibliographic records (as a complement to terms from LCGFT, and as an eventual replacement for LCSH subject headings that include medium and genre/form terms).