Notes that the U.S. General Services Administration (GSA) is the Federal Government's landlord and manages the largest portfolio of general office space in the USA. Examines the GSA's policy of utilising energy efficient building envelopes and its energy conservation standards. Presents the studies of a selected group of government buildings. These range from a small border station to a million-plus ft² Social Security Administration building. Offers illustrations of how the variety of building envelopes have been studied and renovated to bring their thermal envelopes up to more efficient levels.