Data and well-constructed measures quantify suboptimal quality in health care and play a crucial role in improving quality. Measures are useful for three major purposes: (1) driving improvements in outcomes of care by prioritizing and selecting appropriate interventions, (2) developing comparative quality reports for consumer and payer decision making and health system accountability, and (3) creating incentives that pay for performance. This article describes the current landscape for measurement in pediatrics compared to adult care, provides a case study of the development and application of a publicly available and federally funded pediatric indicator set using routinely collected hospital discharge data, and addresses challenges and opportunities in selecting and using measures as a function of intended purpose.