Great clarinet virtuosi have always been involved in the expansion of the repertoire for their instrument. In some cases they were themselves gifted composers--a good example being Franz Tauch--but their greatest contribution by far has been their ability to inspire other, better composers to devote the time and creative energy necessary to the composition of major works for an instrument not usually thought of as a major solo medium. Johann Simon Hermstedt's collaboration with Louis Spohr is a lesser known example of such composer-clarinet virtuoso partnerships which have included, among others, Mozart and Stadler, Weber and Baermann, and Brahms and Muehlfeld.