This report maps the regulatory features underpinning prosumer activities in Germany. It is structured according to a case study design which was developed to compare different countries and to draw respective lessons on policies which enable the prosumer uptake. With a total installed capacity of 38 GW (2015) PV power has reached a stage of systemic importance for the whole power system. Although residential PV (<10 kWp) accounts for only 13 percent of total installed PV capacity, it is an important segment for several reasons. “Prosuming” — although never defined as an official term in Germany — is both a subject and a driver of the adaptive legislation on the RES support scheme and on system integration of RES. It is the result of a dynamic incentive structure set by both regulatory provisions as well as by market developments and the permanent interplay between these factors, rather than as a result of a targeted prosumer policy. Thus, the challenge this case study is confronted with is to map these factors and their respective interplay over a rather long period of time.