The Smart Grid facilitates integration of supply- and demand-side services, allowing the end-use loads to be dynamic and respond to changes in electricity generation or meet localized grid needs. Expanding from previous work, this paper summarizes the results from field tests conducted to identify demand response opportunities in energy-intensive industrial facilities such as data centers. There is a significant opportunity for energy and peak-demand reduction in data centers as hardware and software technologies, sensing, and control methods can be closely integrated with the electric grid by means of demand response. The paper provides field test results by examining distributed and networked data center characteristics, end-use loads and control systems, and recommends opportunities and challenges for grid integration. The focus is on distributed data centers and how loads can be “migrated” geographically in response to changing grid supply (increase/decrease). In addition, it examines the enabling technologies and demand-response strategies of high performance computing data centers. The findings showed that the studied data centers provided average load shed of up to 10% with short response times and no operational impact. For commercial program participation, the load-shed strategies must be tightly integrated with data center automation tools to make them less resource-intensive.