This volume is a collection of background papers and materials prepared for workshop participants engaged in empirical research on the topic of "informed consent with subjects of uncertain competence." The first three papers consider the minimum competence needed to consent to or refuse participation in research, including a philosophical overview, a legal overview, and a psychiatric overview. The fourth paper, a review of the literature for empirical studies on competence and consent, highlights questions which have not been addressed as well as findings which require replication and further investigation; a supplementary, expanded bibliography follows this paper. The final paper is a summary of the workshop discussion in which participants identified an agenda for future research, including the five major areas considered most deserving of attention and practical methodologic considerations for investigators planning research in these areas. The appendix contains a brief paper describing new implications for informed consent, a presentation of the regulations on consent, the original workshop agenda, and a list of workshop guests. (Author/NRB)