Objective: To evaluate the pharmacokinetics, safety and efficacy of sertraline in children (6 to 12 years old) and adolescents (13 to 17 years old), Method: Children (n = 29) and adolescents (n = 32) with major depression, obsessive-compulsive disorder (OCD), or both received a single dose of 50 mg of sertraline followed, 1 week later, by 35 days of sertraline treatment as follows: (1) either a starting dose of 25 mg/day titrated to 200 mg/day in 25-mg increments or (2) a starting dose of 50 mg/day titrated to 200 mg/day in 50-mg increments. Sertraline and desmethylsertraline pharmacokinetics were determined approximately weekly, and efficacy measures were assessed before drug administration and at the end of treatment. Results: Mean area under the plasma concentration-time curve (AUG), peak plasma concentration (C-max), and elimination half-life (t(1/2)) for sertraline and desmethylsertraline were similar to previously reported adult values. No titration-dependent pharmacokinetic or safety differences were seen. White C-max and AUC(0-24) were greater for children versus adolescents, these differences disappeared after parameters were normalized for body weight. Sertraline was well tolerated in both children and adolescents, with adverse experiences similar to those previously reported by adult patients, Efficacy measurements indicated improvement (p < .001) in depression and OCD symptomatology. Conclusions: Sertraline can be safely administered to pediatric patients using the currently recommended adult titration schedule.