Here, the writing committee was charged with developing measures to benchmark and improve the quality of one of cardiology s most common and important procedures: percutaneous coronary inter- vention (PCI). In this task, the ACC/AHA Task Force on Performance Measures partnered with representatives from several other organizations, including the Society for Cardiovascular Angiography and Interventions (SCAI), the American Medical Association (AMA) Convened Physician Consortium for Performance Improvement (PCPI), and the National Committee for Quality Assur- ance (NCQA). These bodies provided invaluable input in the development and review of these measures. The writing committee was instructed to follow the methodology of performance measure development (1,2) and to assure that the measures developed were aligned with national standards so as to promote harmony across measures. The writing committee was also charged with constructing measures that maximally capture multiple important aspects of quality (timeliness, safety, effec- tiveness, ef ciency, equity, and patient-centeredness) while minimizing the reporting burden imposed on participants. As in other cases, all selected measures pose potential challenges to implementation that could result in unin- tended consequences. The manner in which these issues are addressed is dependent on several factors, including the measure design, data collection method, performance attribution, baseline performance rates, reporting methods, and incentives linked to these reports. These imple- mentation challenges are appropriately discussed in indi- vidual sections dedicated to each of the measures. These new performance measures for PCI are notable for several reasons. First, the writing committee considered the key initial question of whether performing the proce- dure was appropriate, in line with a growing body of evidence in this area. 