The presentation is about the decision-making that underlies changes in the operation and stock of technical infrastructure in office buildings. The findings are based on a nation-wide survey of electricity consumption in Swiss office buildings over the period 1986 - 1996. Changes in the stock and the operation of equipment, which I refer to as energy-relevant events, were reconstructed in terms of their impact on electricity consumption, the decision-makers involved and the extent to which energy was considered when the event took place. Energy is not a consideration in most of the decisions related to a change in the stock or operation of equipment. In terms of a theory of action, energy consumption tends to "happen" rather than being consciously chosen. However, energy programs can influence the way energy-relevant decisions are taken by, for example, ensuring that members of the service staff in the organization are given technical help when new equipment is purchased and serviced. Energy conservation should focus on making technical infrastructures rather than on end-use.