This survey was undertaken as part of the initial phase of a larger market design project. The goal of the project is to design a wholesale electric power market such that electric energy storage (EES) resources are permitted to participate and receive compensation that is commensurate with the benefits they provide to the grid. This survey compares and contrasts 3 operating reserve markets in the seven U.S. ISO/RTO-managed electric energy regions. The reserve market categories employed in each energy region are placed into a common framework. The terminology used for reserve markets in each region, as well as the characteristics of these markets, is discussed. Finally, the market procedures currently in place in the seven energy regions for the procurement, settlement, and allocation of costs for reserves are examined.keywords: Power market design, ancillary services, operating reserve, frequency control, and electrical energy storage.4 Acknowledgment