The current study examined the effect of client sexual orientation and gender role on psychologists’ clinical judgment. A secondary purpose was to examine the extent that psychologist heterosexual identity development status affects the level of heterosexist judgment error displayed when working with lesbian and gay male clients. It was hypothesized that psychologists’ clinical decisions will differ as a result of client sex, client sexual orientation, and client gender role when therapist heterosexual identity development status is controlled for, with psychologists providing significantly different clinical judgments (as measured by diagnostic impression ratings, global and relational functioning ratings, and therapist reported client attractiveness) for lesbian and gay male clients and those displaying cross gendered gender roles than heterosexual female and male clients and those displaying gender-congruent gender roles. It was also hypothesized that psychologist heterosexual identity development status and client sexual orientation together are better predictors of the variation observed in psychologist clinical decisions than client sexual orientation alone. Eight hundred randomly selected members of the American Psychological Association, were presented with a clinical vignette describing fictions client seeking psychological services. The vignettes were identical except for client sex (female or male), sexual orientation (heterosexual or lesbian/gay), and gender role (feminine or masculine), which were manipulated to produce eight different vignettes. After reviewing the vignette, participants provided their diagnostic impressions of the client, rated the overall attractiveness of the client, and completed a measure designed to assess their level of heterosexual identity development. One hundred and thirty-five participants completed the study's materials and were included in the main analyses. Results of the randomized 2 (Client Sex) x 2 (Client Sexual Orientation) x 2 (Client Gender Role) multivariate analysis of covariance (MANCOVA), controlling for psychologist heterosexual identity development status, found that psychologists significantly differed in their assessment of lesbian and gay male clients and heterosexual female and male clients on a variety of clinical factors. Results of a series of multiple linear regressions found that psychologist heterosexual identity development status and client sexual orientation together were better predictors of the variation observed in psychologist clinical decisions than client sexual orientation alone.