The federal government's demand for information technology (IT) is ever increasing. In recent years, as federal agencies have modernised their operations, put more of their services online, and improved their information security profiles, their need for computing power and data storage resources has grown. Accordingly, this growing demand has led to a dramatic rise in the number of federal data centres and a corresponding increase in operational costs. In response, the Office of Management and Budget's (OMB) Federal Chief Information Officer (CIO) launched the Federal Data Center Consolidation Initiative (FDCCI) in 2010 to reduce the growing number of centres. This book reports on the progress and challenges of the 24 agencies required to participate in the Data Center Optimization Initiative (DCOI).