Although research on assertion has made important advances in our understanding of young children's behavior within their peer group, there has been a significant limitation in that prior studies have generally not given attention to the gender specific social goals of girls. To advance the literature, this short-term longitudinal study uses a naturalistic observational measure of assertion, which includes assessments of "relationally assertive" behaviors. This multi-method study uses naturalistic observations of aggression and assertion (i.e., over 8,860 min or 148 h of total observation) and teacher reports of assertion and sociometric status. Findings from the preschool sample (M = 49.68 months old; S.D. = 7.66) indicate that aggression subtypes and assertion strategies are related but conceptually unique constructs with differential predictions to indices of sociometric status. Ways in which these findings extend the developmental and early childhood literature are discussed.