This paper critically reviews over 30 years of psychological testing of transsexualism, during which time 41 studies have been published. A review of the psychological tests and methodology employed, the search for an adequate control group, and an analysis of the findings are presented. It is argued that we have reached a critical point in transsexual research. Researchers must reconsider the "hit or miss" approach to psychological testing with transsexuals and relate psychological testing to the actual clinical phenomenon of transsexualism; addressing the newer conceptualizations of transsexualism as a variant of borderline pathology.