Research has shown that every year 30,000 European patients suffer preventable harm during treatment. It is estimated there were potentially 1,735 avoidable deaths in 2004. The financial cost of avoidable adverse events is reckoned at €167 million, 1% of hospitals’ total budget, due to longer hospital stays and additional treatment. Many of these adverse events relate to handoff in care. Poor continuity of clinical care (with multiple provider involvement), either at a patient’s referral to a hospital by a primary care specialist or at a patient’s discharge from the hospital, is a critical aspect of a patient’s care. Incomplete handoffs to a secondary/tertiary care unit or discharge from hospital can lead to adverse events for patients that may ultimately lead to either life threatening situations during treatment/surgery or avoidable treatment and / or re-hospitalizations after the patient’s discharge. Care transitions are especially important for vulnerable groups as the elder and the very young as for high-risk patients with multiple co-morbidities. The overall objective the HANDOVER project is optimize the continuum of clinical care at the primary care hospital interface by reducing unnecessary and avoidable treatment - medical errors and loss of life, by identifying and studying best practices and creating standardized approaches to handoff communication at the primary care hospital interface and measuring the effectiveness of these practices in terms of costs and impact. Handoffs take as many forms as there are handoff scenarios. The idea of developing a single approach for all handoffs is not likely to be possible due to the diversity and complexity of healthcare. HANDOVER will therefore aim at providing standardised basic elements in handoff processes, which can be tailored to meet local and/or institutional needs for flexibility.