This chapter examines the concerns of management, in relation to the energy performance of building. It discusses some of the impediments and opportunities facing those engaged in building energy management. The chapter summarizes the approach taken by a range of government agencies in the US, the U.K., Canada, and New Zealand to the energy management of large numbers of buildings. It describes two building selection techniques for energy conservation programs covering large groups of buildings. The chapter also describes the main elements of a few building energy management programs. It provides an insight into the way various agencies have managed the energy performance of their buildings. The chapter examines a simple index, which can be calculated with a minimum amount of physical and energy data about the buildings. This index can be used to rank buildings according to their energy conservation potential.