Three separate sets of meta-analyses were conducted of studies testing for gender differences in adults' talkativeness, affiliative speech, and assertive speech. Across independent samples, statistically significant but negligible average effects sizes were obtained with all three language constructs: Contrary to the prediction, men were more talkative (d = -.14) than were women. As expected, men used more assertive speech (d = .09), whereas women used more affiliative speech (d = .12). In addition, 17 moderator variables were tested that included aspects of the interactive context (e.g., familiarity, gender composition, activity), measurement qualities (e.g., operational definition, observation length), and publication characteristics (e.g., author gender, publication source). Depending on particular moderators, more meaningful effect sizes (d > .2) occurred for each language construct. In addition, the direction of some gender differences was significantly reversed under particular conditions. The results are interpreted in relation to social-constructionist, socialization, and biological interpretations of gender-related variations in social behavior.