This book outlines a simple and easy-to-follow process for auditing building operation to identify and reduce energy consumption. It explains the operational and cost-based opportunities, assessing the current conditions, analyzing the opportunities, and reporting the findings and documenting the plan. The book discusses the different building components and systems and how they affect energy efficiency and describes the operational energy efficiencies that can be gained by implementing no cost changes or alternate maintenance activities already funded. Capital improvement opportunities, and evaluating Return on Investment and life cycle replacement of equipment are also covered.