With the publication of Crossing the Quality Chasm: A New Health System for the 21st Century, the Institute of Medicine (IOM) enshrined patient centeredness as 1 of 6 distinct dimensions of health care quality.1 In the subsequent decade, patient centeredness gained acceptance as a quality dimension among patients and health care providers, but broad agreement on how to measure patient centeredness and its impact on health outcomes has lagged.2 If you ask most health system administrators to define patient centeredness, they would likely invoke Justice Potter Stewart by answering “I can't define patient centeredness, but I know it when I see it.” As a result, hospitals routinely advertise a “patient-centered approach” to care without actually communicating specific attributes that confirm their patient centeredness or demonstrate how patient centeredness leads to better patient experiences or outcomes.3