Eighteen elementary school children assessed the pleasantness and perfumed aspect of familiar peers' odors, sampled through tee shirts worn without modification of hygienic habits. The participants were also requested to categorize the odors by sex and to recognize those of several target classmates varying in sex and socioemotional status (the participant's most preferred classmate vs. a mere acquaintance). The ratings of odors by familiar peers appeared consistent with those obtained from nonfamiliar peers and adults and varied according to the sex of wearer of the tee shirts. For the five categories of peers examined, as well as for the participants themselves, olfactory recognition was better than chance. Moreover, it was higher for the same-sex preferred peers than for the others only for the female perceivers. The results are discussed in terms of their behavioral relevance for peer relationships, focusing especially on (a) the relations between sex differences in odors and gender development and (b) the function of olfactory memory in the emotional regulation of friendships.