This paper examines the requirements for designated buildings and the mechanisms for implementation of energy conservation programs in accordance with the Energy Conservation Promotion Act of Thailand. It then reviews the details of energy audits and implementation of energy conservation of designated commercial buildings and small government buildings. Through use of the DOE-2 simulation program and reference building models developed from energy audit information, it is shown that whole building retrofit is more cost effective than adopting individual options. It also points out that mobilizing involvement of the occupants of a building is a necessary and integral part of a successful energy conservation program. The paper also suggests means to overcome the present impediments to successful implementation of the programs.