Motivations and roles for sub-national governmental participation in managing climate change

States and regions provide flexibility and innovation in managing climate change. This is exemplified by energy conservation, transportation, forestry, land use, regional planning, waste management policies and programmes to promote lifestyle changes. Problematically, however, subnational government roles vary considerably among countries, depending on the division of authority between central government and regions. For example, in federal systems such as the USA, states can serve as policy 'laboratories'. This may be less true in unitary systems. We explore sources of this vriation and its significance for understanding sub-national climate change activities.