Six school districts in California provided data on the Public School Version of the Adaptive Behavior Scale for 373 children, ages three through six, who were enrolled in regular and trainable mentally retarded (TMR) preschool programs. The results of the study are reported as means and standard deviations of the domain scores for Part One and Part Two, and as standard scores for each reference group. In response to concern about the difficulties in interpreting Part One and Part Two where raw scores are inversely correlated, the scale for Part Two was presented so that the higher the score on both parts, the better the level of adaptive behavior functioning. It was concluded that the differences between mean scores for the regular and TMR samples attests to the validity of the scale for evaluation of individual preschool children. (Author/BW)