Health care clinicians successfully apply proven medical evidence in common acute, chronic, or preventive care processes less than 80 percent of the time. This low level of reliability at the basic process level means that health care's efforts to improve reliability start from a different baseline from most other industries, and therefore may require a different approach. This paper describes The Institute for Healthcare Improvement's (IHI) current approach to improving health care reliability, including a useful nomenclature for levels of reliability, and a focus on improving reliability of basic health care processes before moving on to more sophisticated high reliability organization concepts. Early IHI work with a community of health care reliability innovators has identified four themes in health care settings that help to explain at least a portion of the gap in process reliability between health care and other industries. These include extreme dependence on hard work and personal vigilance, a focus on mediocre benchmark outcomes rather than process, great tolerance of provider autonomy, and failure to create systems that are specifically designed to reach articulated reliability goals. This paper describes our recommendations for the initial steps health care organizations' might take, based on these four themes, as they begin to move toward higher reliability.