Health and medical informatics encompass a very broad field that is rapidly developing in both its research and operational aspects. The discipline has many dimensions, including social, legal, ethical and economic, and consequently, information technology application in healthcare has a long history, triggered from two separate areas of interest. On one hand, the development of medical instruments has incorporated information technology in a vast number of instances. On the other hand, requirements on the registration and processing of medical services and hospital bills have led to extensive EDP-facilities, Hospital Information Systems (HIS) and ancillary registration systems. This book, Effective Healthcare Information Systems puts a special emphasis on issues dealing with the most recent innovations such as telemedicine, Web-based medical information and consulting systems, expert systems and artificial intelligence.