Evidence syntheses use multidisciplinary and intersectoral sources of evidence to support policy-making. The Health Evidence Network (HEN) has supported and strengthened the use of evidence in health policy-making in the WHO European Region since 2003. The HEN synthesis report series responds to public health questions by summarizing the best available global and local findings from peer-reviewed and grey literature, as well as policy options, and proposes general directions, strategies and actions for consideration. This resource has been developed to outline key approaches, methods and considerations for a HEN evidence synthesis to support the systematic and routine use of the best available evidence for decision-making relevant to the needs of public health decision-makers. It proposes approaches that hold both scientific rigour and practical applicability for individuals and institutions that perform, commission, review and/or publish evidence syntheses.