“From waste to nutrient management” – visions, strategies, test runs for a sustainable biowaste management in Berlin according to the cradle-to-cradle principle. Together with EPEA GmbH, Prof. Michael Braungart and Dr. Christoph Semisch, feasibility concepts were drafted, building blocks for the image change “From disposer to value creator” were developed and practical field trials were carried out for the Berliner Stadtreinigungsbetriebe (BSR).