The "Kapellmeister" in Dresden at that time was Johann David Heinichen. Because Heinichen was often ill, Zelenka managed the sacred music in Dresden. When Heinichen died in 1729, Zelenka became an acting "Kapellmeister". He finally became a "Kapellmeister" in 1734. In 1726, Zelenka started a list of works composed by the composers in Dresden. This list is called the "Inventarium". It is an important document for Dresden baroque music. 