The Yale Children's Inventory (YCI), a parent-based rating scale, and the scales derived from it have been developed to identify and measure multiple dimensions of learning disabilities with particular emphasis on attentional deficits. Scale construction was based on factor-analytic procedures. Measures of internal consistency, test-retest reliability, and coefficients of congruence support the reliability and stability of the 11 scales. A discriminant function classified normal and learning-disabled children with a relatively high rate of accuracy. The relationship and content of the three relevant YCI scales were compared to the DSM-III diagnostic categories for ADD. As operationalized, DSM-III criteria for hyperactivity formed a cohesive factor, while criteria for attention and impulsivity were not distinguishable from each other since they loaded together on a single factor. In contrast, the equivalent YCI scales for attention, impulsivity, and hyperactivity were found to be distinct.