The Institute of Medicine’s (IOM’s) release of the reports To Err is Human and Crossing the Quality Chasm in 1999 and 2001, respectively, were markers of a tipping point in U.S. health care. Prior to that time, “quality” in health care had largely been defined by innovation and cutting-edge diagnostic and therapeutic interventions. The challenge issued by these IOM reports and the “quality movement” in general was to continue such innovations, but at the same time to markedly improve the reliability and safety of the delivery of the more routine elements of care. Central to the new dogma was a growing appreciation that the limits of human performance are such that high-reliability care cannot be based on a model of individual perfection, but rather requires an approach built on highly effective teamwork and intentional process redesign. While tools ranging from simple checklists to sophisticated disciplines such as Six Sigma and Lean can be extremely helpful, culture plays a central role in achieving these goals.