This study examined the relationship among Wechsler and Stanford-Binet IQ scores, Wide Range Achievement Test scores, and Adaptive Behavior Scale scores for a sample of 129 institutionalized mentally retarded children and adolescents in a Special Education program. Significant but small to moderate correlations (.26 to .50) were obtained between WRAT and IQ scores and between behavior scale scores and IQ. Each measure differentiated between special education training levels. Use of the Adaptive Behavior Scale may provide an important supplement to more frequently used screening procedures such as IQ and achievement scores.