Legal, ethical, and procedural guidelines for the participation of mentally retarded people in research were solicited from 167 agencies, of which 67 responded. A variety of documents was cited by the respondents. The documents appeared to establish the outside limits of ethical practice but did not establish actual procedure. Furthermore, the documents tended to address research as broadly defined and did not emphasize guidelines for survey or statistical summary research as opposed to manipulative experimentation. The issue of direct benefit of research to mentally retarded subjects as a condition for participation is examined with the review of research proposals, participant consent, and the use of substitute decision-makers for persons judged incompetent. (Author/CM)