A 2-part study examines the influence of normative messages on college males' hand washing perceptions and behaviors. Study 1 tests for the appropriateness of hand washing as a target of social norms campaigns and tests messages designed to change perceived descriptive norms. Results indicated that hand washing behavior is appropriate for health promotion through normative influence. Study 2, a field experiment observing frequency and efficacy of hand washing behaviors, manipulates behavioral privacy and normative messages in public restrooms. Results provided no evidence for the hypothesis that social norms should be most influential for publicly enacted behaviors. Messages increased hand washing frequency, length of time water was run, and attitudes relative to control. Across all conditions, poor-quality hand washing was evidenced. (Contains 4 tables and 8 notes.)