At the MPI for Medical Research, physicists, chemists and biologists create knowledge of long-term relevance to basic medical science. With the arrival of three new directors in 2015/16, the institute has a new unifying theme: observing and controlling the vastly complex macromolecular interactions in the context of cells - both in health and disease. The presently four departments contribute to this goal through their complementary expertise: optical microscopy with nanometer resolution (Stefan Hell), the design of chemical reporter molecules (Kai Johnsson), macromolecular structure determination (Ilme Schlichting), cellular, materials and biophysical sciences (Joachim Spatz). The institute has a distinguished history of fundamental breakthroughs, evidenced by six Nobel Prizes awarded to its researchers since its foundation.