The goal of improving patient safety has led to a number of paradigms for directing improvement efforts. The main paradigms to date have focused on reducing injuries, reducing errors, or improving evidence based practice. In this paper a human factors engineering paradigm is proposed that focuses on designing systems to improve the performance of healthcare professionals and to reduce hazards. Both goals are necessary, but neither is sufficient to improve safety. We suggest that the road to patient and employee safety runs through the healthcare professional who delivers care. To that end, several arguments are provided to show that designing healthcare delivery systems to support healthcare professional performance and hazard reduction should yield significant patient safety benefits. The concepts of human performance and hazard reduction are explained.