This guide provides recommendations for local governments to reduce their communities' greenhouse gas emissions. It discusses community design from a smart growth perspective—including factors such as physical layout; proximity and accessibility to goods, services, workplaces, and schools; and the materials and designs used in building and infrastructure—and their impact on greenhouse gas emissions. The guide describes the benefits of smart growth; planning and design considerations; stakeholders; foundations for smart growth program development; implementation strategies; investment and funding opportunities; federal, state, and other programs that may be able to help local governments with information or financial and technical assistance; and two case studies.