10 Data and Mined-Knowledge Interoperability in eHealth Systems Kamran Sartipi, Mehran Najafi and Reza S. Kazemzadeh McMaster University Canada 1. Introduction The advancement of software development through component technology and system integration techniques has resulted in a new generation of very large software systems. This new paradigm has intensified challenges including interoperability of heterogeneous systems, sharing and reusing services, management of complexity, and security and privacy aspects. Examples of such globalized systems include: communication systems, banking systems, air traffic systems, transportation systems, and healthcare systems. These challenges require new development and management technologies and processes that fulfill the emerging demands in the networked systems. Modern healthcare is experiencing major changes and as a result traditional conceptions are evolving: from health provider-centric to patient and family-centric; from solitary decision making to collaborative and evidence-based decision making; from decentralized and generalized care to centralized and specialized care. The need for better quality of service, unique identification of health records, and efficient monitoring and administration requires a uniform and nation-wide organization for service and data access. Among other requirements, these changes require extensive assistance from modern software and information technology domains. Until recently there has been little attention to the IT infrastructure of healthcare systems. However, global trends are shifting healthcare towards computerization by developing electronic health record systems, IT- standardization through HL7 (Health Level 7) initiatives and nation-wide infrastructure specifications (Canada Health Infoway) and utilization of current evidences in decision- making processes. Most current systems are monolithic, isolated, paper-based, error-prone legacy systems which cause huge costs for the governments and healthcare organizations. The new systems need to take advantage of modern information and distributed systems to meet the emerging demands in healthcare environments. As a result governments and private sectors are investing on healthcare information technology infrastructures to reduce huge costs of the existing systems and improve the quality of public care. Health informatics (eHealth) is a new field which embodies a variety of techniques in information and knowledge management, data mining, decision support systems, web services, and security and privacy. Therefore, researchers with multi-disciplinary research interests from these fields need to collaborate in order to advance the state of the art in eHealth. In this chapter, we attempt to cover the core technologies that need to work Open Access Database www.intechweb.org Source: Data Mining in Medical and Biological Research, Book edited by: Eugenia G. Giannopoulou, ISBN 978-953-7619-30-5, pp. 320, December 2008, I-Tech, Vienna, Austria