In this paper the need for review (ethical) committees is elaborated to include a discussion of their composition and function. In some institutions more than one such committee may be set up, a departmental ethical committee and one which studies the projects of all the departments concerned. By considering proposed research before it is started patients or volunteers are protected from injury, discomfort, and inconvenience, and the scientific validity of a clinical experiment can be scrutinized. A list of possible criteria (...) for the work of ethical committees is given. (shrink)