This book is an introduction into methodology and practice of analysis, design and implementation of distributed health information systems. Special attention is dedicated to security and interoperability of such systems as well as to advanced electronic health record approaches. In the book, both available architectures and implementations but also current and future innovations are considered. Therefore, the component paradigm, UML, XML, eHealth are discussed in a concise way. Many practical solutions specified and implemented first in the author's environment are presented in greater detail. The book addresses information scientists, administrators, health professionals, managers and other users of health information systems.