This document is one of the outcomes of the Third International Conference on Early Warning in 2006, held in Bonn, Germany. It presents a series of practical checklists that cover elements, actions and good practices to assist in developing, evaluating or refining early warning systems. It is presented as a non-technical reference tool rather than an extensive 'how-to' list for designing early warning systems. The document also provides background information on early warning, which includes an overview of four key themes (risk knowledge, monitoring and warning service, communication, response capability), as well as cross-cutting issues such as governance and involvement of local communities. It also outlines the roles of key actors (such as local governments and international bodies) within each theme,, without discussing any overlap of responsibilities and how they relate to the different elements of early warning systems.