This article describes the multifaceted response of Dana-Farber Cancer Institute after a highly publicized medication error in 1995. The authors review a series of interventions designed through the multidisciplinary efforts of nursing, pharmacy, physician, administrative, and other clinical staff. Factors discussed include the role of the patient and family, the need for executive leadership, root cause analyses, a shift to nonpunitive environments, and development of better processes for care. The authors share how a single adverse event catalyzed 7 years of efforts to bring patient safety to the forefront and explain what future steps must occur in the area of patient safety.