Traditionally, social psychology has conceptualized sex and gender as subject variables with sex as a biological substrate and gender as a sociocultural consequence of sex. These ideas rest on the assumption of two distinct biological categories. However, gender is better thought of in dialectical rather than oppositional terms. Gender is both internal (traits, beliefs, personality) and external (roles and social organization). One aspect of gender cannot be isolated but must be studied in relation to the sex/gender system, which represents a social, psychological, biological, economic, and cultural totality. From a feminist theoretical perspective, gender becomes the starting point of analysis, focusing on the sex/gender system and how it produces sexed and gendered individuals. Social psychology from a feminist perspective would examine sex and gender within their specific cultural-historical meanings. Research methodologies must also assume a relational orientation, rather than the traditional laboratory-based experimental designs. Sex differences must be put within a theoretical framework connecting individual behavior with the structural arrangement of gender. Social psychology can provide the point of interconnection between external social structures and individual experience, thus providing a synthesis between the study of gender and feminist theory. (BL)