This paper presents a summary of an on-going research project concerned with doctor-patient communications. Of specific interest are doctors' communications of information about illness to the patient. The communication of information in medical care situations is considered to be, at certain levels, analogous to the purposive, instructional communications in education.Sociological considerations guiding this research are summarized under four headings: (1) problems of uncertainty and power; (2) the definition of information; (3) sociolinguistics and the diffidence of the sick poor; and, (4) ethnomethodology and common sense constructs. The doctor-patient relationship is viewed as a micro-political situation in which information control is used, at least in part, to maintain patterns of dominance and subordination.The overall methodological objective of this research is to develop a research design, linked to these research objectives, which allows reproducible and generalizable conclusions about the informative process in a variety of clinical settings. This preliminary paper includes a discussion of technical problems arising from the study of doctor-patient relationships and communications; preliminary results of studies of non-verbal communication; and, qualitative themes in the informative process.