Five hundred and sixty-two, 16- to 17-year-old consecutive inductees into the Israeli Army, constituting a random sample of their cohort, were screened for obsessive-compulsive disorder (OCD), Tourette's syndrome, transient tics (TT), chronic multiple tics (CMT), and attention-deficit hyperactive disorder (ADHD). Two child psychiatrists interviewed the subjects, using screening items from structured interviews that implement DSM-III-R diagnostic criteria. For OCD, a point prevalence of 3.6% was found, 3.9% for ADHD, 1.8% for CMT, and 1.6% for TT. For ADHD, TT, and CMT, but not for OCD, there was a significantly higher prevalence for males than for females. Among the OCD individuals, there was an elevation of TT, CMT, and Tourette's syndrome relative to the population rates.