The U.S. Energy Services Company (ESCO) industry is often cited as the most successful model for the private sector delivery of energy-efficiency services. This study documents actual performance of the ESCO industry in order to provide policymakers and investors with objective informative and customers with a resource for benchmarking proposed projects relative to industry performance. We have assembled a database of nearly 1500 case studies of energy-efficiency projects - the most comprehensive data set of the U.S. ESCO industry available. These projects include $2.55B of work completed by 51 ESCOs and span much of the history of this industry.