Detailed plant performance analyses were conducted using unit and plant performance characteristics and 1-minute plant operational data from 2008, 2009, and 2010 for five pumped-storage plants. These five case studies encompass three markets (MISO, NYISO, and PJM) and one non-market region (Southeast area). Owners for the five plants include three investor-owned utilities, one state power authority, and one federal power corporation. This report describes results from detailed performance analyses that evaluated reductions in overall plant efficiencies under a variety of operation-related and market-related conditions for the plants. Results from this report show that the non-market operations of pumped-storage plants by vertically integrated utilities resulted in more efficient performance of their plants than the market-based utilities. Opportunities are identified for both market improvements and plant improvements to reduce avoidable suboptimization of pumped-storage plants.