Medical research with incompetent patients which is expected to yield only questionable or no individual benefit (and which is often wrongly equated with non-therapeutic research) remains a difficult and controversial problem. This is reflected in the fact that such research is legally admissible in some countries such as France and England, but is questionable or prohibited in other countries, eg, Germany. Such research can only be justified ethically if the need for it is set forth according to defined criteria, and if defined protective criteria are fulfilled, particularly to ensure that the research-related instrumentalisation of the patient is held in check by observing respect for the patient's dignity, to ensure that research does not involve more than minimal risks and negligible stress for the individual participant, and that the patient's refusal to participate is accepted. A broad international consensus exists with regard to these criteria [9, 21, 26, 41]. But concepts and definitions as to what constitutes benefits and risks, as well as criteria and procedures in weighing benefits against risks, and, not least of all, the weighing of individual benefit against societal benefit, require clarification. The question must also be satisfactorily answered: who is to do the weighing? But above all, it must be ensured by professional education that this process of checks and controls is effectively carried out in day-to-day medical-scientific life.