Managing patient care records has become an increasingly complex issue with the widespread use of advanced technologies. The vast amount of information for every routine care procedure must be securely processed within different databases. Clinical information systems (CIS) address the need for a computerized approach in managing personal health information. Hospitals and public or private health insurance organizations are continuously upgrading their database and data management systems to more sophisticated architectures. The possible support of today's large patient archives and the flexibility of a CIS in providing up-to-date patient information and worldwide doctors' collaboration, has leveraged research on CIS in both the academic and the government domains. At the same time, it has become apparent that patients require more control over their clinical data, these being either the results of clinical examinations or medical histories. Due to the large amount of information that can be found on the Internet and the free access to medical practitioners and hospitals worldwide, patients may choose to communicate their information so as to obtain several expert opinions regarding their conditions. Given the sensitive nature of the information stored and inevitably in transit, security has become an issue of outmost necessity. Numerous EU and US research projects have been launched to address security in CIS (e.g., EUROMED, ISHTAR, and RESHEN), whereas regulatory compliance to acts such as the HIPAA has become an obligation for centers moving to CIS. Copyright © 2008 John Wiley & Sons, Ltd.