Providing wastewater and drinking water service to citizens requires energy—and a lot of it. The twin problems of steadily rising energy costs and climate change have therefore made the issue of energy management one of the most salient issues facing wastewater and water utilities today. Energy management is also at the heart of efforts across the entire sector to ensure that utility operations are sustainable in the future. More and more utilities are realizing that a systematic approach for managing the full range of energy challenges they face is the best way to ensure that these issues are addressed on an ongoing basis in order to reduce climate impacts, save money, and remain sustainable. Working closely with a number of utilities and others, the Office of Water at the U.S. Environmental Protection Agency (EPA) is proactively addressing this issue by developing this Energy Management Guidebook for Wastewater and Water Utilities that provides a systematic approach to reducing energy consumption and energy cost. This Guidebook was specifically written to provide water and wastewater utility managers with a step-by-step method, based on a Plan-Do-Check-Act management system approach, to identify, implement, measure, and improve energy efficiency and renewable opportunities at their utilities.