The Aerospace Corporation, the City Government, and the Board of Education of Jersey City have conducted a group of energy-conservation experiments to explore a number of conservation techniques believed to offer quick payback and to be of wide applicability. Experiments include the updating and/or rehabilitation of the energy-consuming features of old buildings and installation of devices designed to minimize energy losses caused by human error or laxity. Specific examples include: upgrading of the deteriorated and inefficient steam-distribution system of the city hall (originally constructed in 1894); an extensive program of reducing infiltration in an old school building; use of several timing devices in connection with heating, ventilation, and lighting systems to encourage energy-conservation practices; retrofit of school classrooms with high-pressure sodium lamps; and demonstration of practical and cost-effective ways of increasing the efficiency of conventional steam boilers. The report presents: the nature of the selected experiments; technical, human, and organizational factors that proved significant in performing and evaluating the experiments; discussions of observations and lessons learned; and general recommendations for an extended program of energy conservation in local governments. It is emphasized that, in retrofit of existing buildings, the unexpected is commonplace; and the habits and attitudes of building occupants are elements of the system that must always be taken into account. This report shows the benefits of energy saving, cost saving, and added comfort that may be attained by retrofitting old buildings, noting typical complications that arise. The effectiveness of the conservation methods is presented in terms of costs relative to effective payback periods calculated from results of their application in Jersey City.