The Deutsche Krebsgesellschaft (German Cancer Society) and the Arbeitsgemeinschaft Deutscher Tumorzentren (Association of German Tumor Centers hold the congress "Quality of Cancer Care" (QoCC) every two years. The focus is on the quality of oncological care. Unlike other events, the QoCC does not address individual aspects. Rather, it is about linking all important topics - from the oncological guideline, to certification and documentation, to clinical studies and health services research. The idea for this congress came from the experience that it is often the interface between the areas where there is friction loss in the quality development of cancer care. The chosen format of the QoCC, a combination of tutorials, lectures, panel discussions and poster presentations, provides an excellent platform for a constructive exchange of ideas and experiences to minimize obstacles and frictional losses.