As psychological research on sexual-minority (i.e., nonheterosexual) adolescents has increased over the past 20 years, it has become increasingly segregated from research on mainstream heterosexual youths, as if the knowledge gleaned from each population had nothing to offer our understanding of the other. To the contrary, understanding of both populations would be greatly improved by integrating investigations of sexual-minority issues into mainstream psychological research on adolescents. I outline 4 weaknesses in contemporary research on sexual-minority youth that stem from--and perpetuate--its historical isolation from mainstream developmental research: misspecification of the populations under study, lack of attention to within-group diversity, failure to test alternative explanations for--and moderators of--"sexual-minority effects," and insufficient attention to the underlying processes and mechanisms through which sexual-minority effects operate. Correcting these weaknesses has important implications for future research on how same-sex and other-sex sexuality shape adolescent psychosocial development and clinical child and adolescent problems.