The present study examined if a short, 22-item teacher rating questionnaire could be used to screen young adolescent boys for psychiatric diagnoses. Subjects were 239 12-year-old boys from a community sample of low socioeconomic status families. Child and parent versions of the Diagnostic Interview Schedule for Children were used to provide DSM-III-R diagnoses. Results show a low to moderate screening value for the Short Social Behavior Questionnaire (S-SBQ) scales, with best results for externalizing disorders. The method used to establish the diagnoses had an impact on the screening efficacy of the S-SBQ, higher prevalence rates resulting in a lower proportion of false-positives for the same cutoff point. Additional research is needed to assess the screening efficacy of the S-SBQ across ages and gender, but results suggest that teacher ratings with the S-SBQ could be used to screen boys with externalizing disorders at the end of elementary school.