Child care centers are a unique context for studying communication about the social and personal expectations about health behaviors. The theory of normative social behavior (TNSB; Rimal & Real, 2005) provides a framework for testing the role of social and psychological influences on handwashing behaviors among child care workers. A cross-sectional survey of child care workers in 21 centers indicates that outcome expectations and group identity increase the strength of the relationship between descriptive norms and handwashing behavior. Injunctive norms also moderate the effect of descriptive norms on handwashing behavior such that when strong injunctive norms are reported, descriptive norms are positively related to handwashing, but when weak injunctive norms are reported, descriptive norms are negatively related to handwashing. The findings suggest that communication interventions in child care centers can focus on strengthening injunctive norms in order to increase handwashing behaviors in child care centers. The findings also suggest that the theory of normative social behavior can be useful in organizational contexts.