Sexual self-schemas are cognitive generalizations about sexual aspects of oneself. In Part 1, a measure of men's sexual self-schema is developed. Studies of test-retest and internal consistency reliability and validity studies of factor analysis, internal structure, convergent and discriminant validity, process, group difference, and change are provided. The construct consists of 3 dimensions: passionate-loving, powerful-aggressive, and open-minded-liberal traits. In Part 2, the data suggest that men's sexual schema is derived from past sexual experience, is manifest in current sexual experience, and guides future sexual behavior. In Part 3, the data document the cognitive processing aspects of sexual schema. Consistent with the investigators' schema research with women, these data substantiate the importance of cognitive representations of sexuality.