District Energy is the local production and distribution of thermal energy used for residential, commercial, and industrial buildings. This guide is an important read for municipal officials, planners, and neighborhood champions interested in building a district energy system in their community. District energy can be a more efficient use of resources, a community economic engine, and increase livability and sustainability of a community if properly planned. The guide details the necessary steps for district energy approval and implementation, such as: objective setting for the plan, gathering district data, defining project boundaries and scale, conducting a feasibility study, financial and business modeling, and policy considerations for the project. The guide provides case studies about districts that completed steps along the district energy planning process.