Sluggish cognitive tempo (SCT) is increasingly recognized as a valid attention disorder distinct from attention-deficit/hyperactivity disorder. The culmination of more than 10 years of research and development, the Barkley Sluggish Cognitive Tempo Scale-Children and Adolescents (BSCTS-CA) is the first empirically based, norm-referenced tool designed to assess SCT symptoms (for example, chronic daydreaming, inability to focus, and lethargy) in the daily life activities of 6- to 17-year-olds. The scale typically takes a parent less than 5 minutes to complete. Detailed instructions for scoring and interpretation are provided.