Behavior problems in 20 preschool children (13 boys, 7 girls) referred to a diagnostic nursery were assessed using parents' ratings. The patterns of behavior problems reported in 4- and 5-yr.-olds parallel those noted for older clinic-referred children (i.e., internalizing difficulties in girls, externalizing difficulties in boys). The most salient behavior problems for 3-yr.-olds involved aggression. Correlations between children's behavior problems and an index of parents' experienced stress were moderate (.44 to .64).