Isaac Posch (1591–1622) was an Austrian composer and organist of the early baroque era. He is chiefly known for his contribution to dance music. Posch worked in Carinthia from around 1614 and built organs in Carniola and Laibach. As a composer Posch was important in the development of the Baroque variation suite having composed fifteen three movement works in a 1618 collection. All of the movements in this collection are personally unique. He also combined five-part pavans with galliards. Posch's Cantiones sacrae consisted of forty-two concertos for different vocal settings for five voices. Five of these songs were also set for obligato instrumentation.
