Professor Rosenthal′s research has centered for over 40 years on the role of the self-fulfilling prophecy in everyday life and in laboratory situations. Special interests include the effects of teacher′s expectations on students′ academic and physical performance, the effects of experimenters′ expectations on the results of their research, and the effects of clinicians′ expectations on their patients′ mental and physical health. For some 40 years he has been studying the role of nonverbal communication in (a) the mediation of interpersonal expectancy effects and in (b) the relationship between members of small work groups and small social groups. He also has strong interests in sources of artifact in behavioral research and in various quantitative procedures. In the realm of data analysis, his special interests are in experimental design and analysis, contrast analysis, and meta-analysis. His most recent books and articles are about these areas of data analysis and about the nature of nonverbal communication in teacher - student, doctor - patient, manager - employee, judge - jury, and psychotherapist - client interaction. He is Co-Chair of the Task Force on Statistical Inference of the American Psychological Association.