A fundamental requirement for achieving continuity of care is commonly accepted to be the integration and interoperability of different clinical oriented systems towards the realization of a “longitudinal” Electronic Healthcare Record. To enable seamless integration of various kinds of IT applications into a healthcare network, a commonly accepted framework based on international relevant standards has become an urgent need. However, there is much marketplace confusion today in the healthcare domain, due to the variety of overlapping or complementary interoperability standards and initiatives, which have evolved over the years addressing integration of applications at different levels. This chapter provides a brief overview of the most relevant Electronic Healthcare Record standards, by examining the level of interoperability and functionality they provide, in terms of context, structure, access services, multimedia support, and security, to provide healthcare decision-makers and system integrators with a clear perspective regarding the capabilities and limitations of each standard.