Although recent attention has focused on the likelihood that contemporary sexual minority youth (i.e., gay, lesbian, bisexual [GLB]) are "coming out" at younger ages, few studies have examined whether early sexual orientation identity development is also present in older GLB cohorts. We analyzed retrospective data on the timing of sexual orientation milestones in a sample of sexual minorities drawn from the California Quality of Life Surveys. Latent profile analysis of 1,260 GLB adults, ages 18-84 years, identified 3 trajectories of development: early (n = 951; milestones spanning ages 12-20), middle (n = 239; milestones spanning ages 18-31), and late (n = 70; milestones spanning ages 32-43). Motivated by previous research on variability in adolescent developmental trajectories, we identified 2 subgroups in post hoc analyses of the early profile group: child onset (n = 284; milestones spanning ages 8-18) and teen onset (n = 667; milestones spanning ages 14-22). Nearly all patterns of development were identity centered, with average age of self-identification as GLB preceding average age of first same-sex sexual activity. Overall, younger participants and the majority of older participants were classified to the early profile, suggesting that early development is common regardless of age cohort. The additional gender differences observed in the onset and pace of sexual orientation identity development warrant future research. (Contains 7 tables, 2 figures and 4 footnotes.)