Patients are increasingly seen by an array of providers in a wide variety of organizations and places, raising concerns about fragmentation of care. Policy reports and charters worldwide urge a concerted effort to enhance continuity, 1 – 3 but efforts to describe the problem or formulate solutions are complicated by the lack of consensus on the definition of continuity. To add to the confusion, other terms such as continuum of care, coordination of care, discharge planning, case management, integration of services, and seamless care are often used synonymously. This synthesis was commissioned by three Canadian health services policy and research bodies. The aim was to develop a common understanding of the concept of continuity as a basis for valid and reliable measurement of practice in different settings.