The correlation between the Adaptive Behavior Scale (ABS) and the Vineland Social Maturity Scale (the Vineland) was investigated using a sample of 98 subjects from a state residential facility for mentally retarded individuals. Pearson correlations between the raw scores of the two scales revealed a high degree of association between the Vineland and Part One of the ABS. The correlation between the Vineland total score and ABS Part One sum score equaled .79. The Part One domain correlations ranged from .44 (Physical Development) to .77 (Language Development), with a mean of .64. Part Two of the ABS showed little relationship to the Vineland. The Part Two total score correlation was .11, and the mean Part Two domain correlations was .20.