This series is directed to healthcare professionals who are leading the tra- formation of health care by using information and knowledge.Launched in 1988 as Computers in Health Care, the series offers a broad range of titles: some addressed to speci?c professions such as nursing,medicine,and health administration; others to special areas of practice such as trauma and ra- ology. Still other books in the series focus on interdisciplinary issues, such as the computer-based patient record, electronic health records, and n- worked healthcare systems. Renamed Health Informatics in 1998,to re?ect the rapid evolution in the discipline now known as health informatics, the series will continue to add titles that contribute to the evolution of the ?eld. In the series, eminent experts,serving as editors or authors, offer their accounts of innovations in health informatics. Increasingly these accounts go beyond hardware and software to address the role of information in in?uencing the transfor- tion of healthcare delivery systems around the world.The series also will increasingly focus on "peopleware" and organizational, behavioral, and societal changes that accompany the diffusion of information technology in health services environments.