In this study, we examined the relationship between psychological androgyny and optimal mental health in a sample of adults seeking career consultation (N = 154). Most earlier research on the subject employed self-report measures of well-being or adjustment. In this study, we employed an "observer-by-proxy" measure of optimal mental health that, although based on self report data, provides an empirically based estimate of ratings that clinicians would make using the California Q-set (Block, 1961/1978). High levels of both masculinity and femininity are associated with higher levels of optimal mental health. These findings represent a rare example of support for the additive androgyny hypothesis and argue for its further study. We also discuss the construct validity of the masculinity and femininity scales we used, and we argue for further study of our mental health measure.