The purpose of this guide is a rational use of anti-infectives. A rational anti-infective therapy has become a complex challenge in view of the constant progress in medicine and the worsening resistance problem. This guideline provides standard recommendations for the prophylaxis and empirical therapy of frequent infections, taking into account current scientific knowledge, but also taking into account the local epidemiology of resistance and pharmaco-economic considerations. Once the microbiological findings have been received, the therapy should be adjusted in line with the clinical course. The guide is not a textbook and is not a substitute for careful clinical assessment of the patient and the adaptation of therapy to individual circumstances in justified cases. The app serves purely for imparting knowledge and does not fulfill any additional medical purpose, such as diagnosis, contraception, monitoring, prognosis, treatment of diseases, etc. in the sense of an active decision-making aid or dosage aid.