In spite of the substantial achievements of modern medicine, infectious diseases are still the major cause of death responsible for about a third of all fatal casualties worldwide. The emergence of “new” diseases like SARS or new influenza highlights the still ongoing battle against infectious diseases, whereas the increase of resistances against all effective classes of antibiotics drastically weakens the chance to prevail. The situation is especially bad regarding tropical diseases like Malaria, Leishmaniasis or Sleeping sickness, that nearly vanished until the 1960s but re-emerge today, as well as for tuberculosis and HIV. These diseases reside mainly in poor countries where the patients cannot afford the costs for medication, a fact that severely discourages the pharmaceutical industry to invest in this field. Hence, the development of novel drugs against infectious diseases is of pivotal importance. For that reason, researchers of four faculties of the University of Würzburg together with the Medical Mission Clinic formed the Collaborative Research Center to search for innovative solutions by joint interdisciplinary approaches.