A previous report that involved one of the authors of this article indicated that Polly's parents sought an evaluation to determine whether she had ADHD. Once diagnosed, the parents wanted to improve her functioning at home, in school, and with friends. The measurement of treatment outcomes, therefore, focused on variables related to such functioning. The recommended practice for assessing children's impairment includes obtaining information from the child's parents and classroom teachers. This should be done with both standardized quantitative (frequency) and qualitative (kinds of behavior) data. Clinicians may find that the best technique for assessing Polly's impairment is to create a short checklist based on the target behaviors. The initial rating scale should reflect all of the presenting problems and be given to all teachers and parents. Based on a discussion of potential costs and benefits, all of the parties involved in Polly's case agreed to a medication trial. Changes in the frequency of positive scores on three "daily report card" (DRC) school-based items became the primary outcome measure. Related assessment issues were the potential bias of adult raters that might influence their ratings and the coordination of the services provided by many professionals involved in the interventions for Polly. DRCs are a clinically feasible way of measuring key behaviors targeted for treatment, and they also involve less rater burden than many other methods. They also directly assess real-world behaviors as they change over time and under various conditions. 27 references