Under German law, consent will be valid only if the physician has provided the patient with the necessary information to take an informed decision. Only an informed patient can exercise his or her right to self-determination in a reasonable manner. German medical law traditionally differentiates between information for safety purposes and information for purposes of self-determination. Only information for purposes of self-determination is a prerequisite for the validity of informed consent; its content is focused on the risks of the proposed medical intervention. Information for safety purposes, by contrast, is a necessary part of the professional medical treatment itself and includes all information required to ensure a successful outcome and the compliance of the patient. The capacity to consent to treatment depends on the patient’s capacity to understand the information provided by the physician. A medical intervention performed without valid consent of the patient is unlawful and constitutes a violation of contractual duties as well as a personal injury.