The Telemann-Werke-Verzeichnis (Telemann Works Catalogue), abbreviated TWV, is the numbering system identifying compositions by Georg Philipp Telemann, published by musicologist Martin Ruhnke.
The genre number indicates the general type or medium of the work.
For example, Telemann's Concerto polonois in B flat major for strings and basso continuo is TWV 43:B3.
Vocal works were catalogued in a similar way by Werner Menke in the Telemann-Vokalwerke-Verzeichnis (Telemann Vocal Works Catalogue), abbreviated TVWV.
Genres of vocal works are numbered from 1 to 25, and usually prefixed by TVWV.