The goal of this study was to learn more about clinicians' experiences with, and perceptions of the utility, validity, and feasibility of standardized outcome measures in practice. Fifty randomly selected clinicians from multiple disciplines and multiple service agencies in a large children's public mental health service system were interviewed individually (n = 30) or in focus groups (n = 20) using semistructured interviews. There was great variability across clinicians in attitudes about empirical methods of treatment evaluation. There was consensus regarding feasibility challenges of administering standardized measures, including time burden and literacy barriers. Although all participants had received scored assessment profiles for their clients, the vast majority reported that they did not use the scores in treatment planning or monitoring. Their suggestions for improved clinical utility of outcome measurement are included. With increased attention and resources devoted to performance outcome assessment, it is concerning that most clinicians perceive little clinical utility of outcome measurement.