The hypothesis is tested that adolescent boys' (mean age of 12.8 years) intrasexual rough-and-tumble play (R&T) is used for dominance and intersexual R&T is used to establish heterosexual relationships. In Study 1, boys' observed R&T was related to both dominance and aggression. In the first half of the school year, R&T occurred primarily between males, possibly to establish dominance. In the second half of the year, both boys and girls engaged in R&T, possibly to establish heterosexual relationships. Counter to the hypothesis, observed aggression increased across the year. In Study 2, youngsters viewed taped R&T bouts in which they were participants or nonparticipants. Participant, more than nonparticipant, males saw R&T as related to dominance whereas participant, more than nonparticipant, females saw it as playful.