Cycling, walking and rapid transit systems are associated with a wide range of potential health benefits that climate assessment needs to consider more systematically. Health benefits may include: physical activity from walking and cycling, which can help prevent heart disease, some cancers, type 2 diabetes, and some obesity-related risks; lower urban air pollution concentrations; lower rates of traffic injury risks for users of dedicated bicycle and pedestrian networks; and less noise stress. Transport systems that prioritize active transport and rapid transit systems, along with better urban land use, also can help improve access for vulnerable groups, including children, the elderly, people with disabilities, and lower wage earners, enhancing health equity. This new WHO report, part of the Health in the Green Economy series, considers the evidence regarding health co-benefits, and risks, of climate change mitigation strategies for transport, as reviewed by the Intergovernmental Panel on Climate Change (IPCC, 2007).