Organ donation from relatives or other persons with a close relationship to the patient has become a fairly routine procedure in many countries. However, donors should be chosen carefully not only to avoid medical or psychosocial risks but also ethically questionable outcomes. Prerequisites for living organ donation are reported together with a short review of the known risks for donors. Under the central maxim of averting harm for the donor, six cases are described to illustrate typical difficulties in the psychosomatic-ethical consultation-liaison service, and our own procedures are discussed. Suggestions are made as to how to approach the information, evaluation and selection of potential donors.