THIS MANUAL IS DIRECTED PRIMARILY TO OWNERS, OCCUPANTS, AND OPERATORS OF COMMERCIAL BUILDINGS AND DESCRIBES A WIDE RANGE OF OPPORTUNITIES AND OPTIONS WITH WHICH TO SAVE ENERGY AND OPERATING COSTS. SUGGESTIONS ARE PRESENTED FOR MINOR MODIFICATIONS TO BUILDINGS AND THEIR MECHANICAL AND ELECTRICAL SYSTEMS; THESE CAN BE IMPLEMENTED PROMPTLY WITH LITTLE IF ANY INVESTMENT COSTS. REQUIREMENTS TO PARTICIPATE IN THIS ENERGY CONSERVATION PROGRAM ARE LISTED SUCH AS IDENTIFICATION OF THE GENERAL CLIMACTIC CONDITIONS, EVALUATION OF THE EXISTING CHARACTERISTICS AND SYSTEMS OF THE PARTICULAR BUILDING, AND ESTIMATION OF THE MAGNITUDE OF ENERGY USAGE. THEN TARGET GOALS CAN BE SET AND STEPS CAN BE TAKEN TO REDUCE ELECTRICAL AND MECHANICAL BUILDING LOADS AND THERMAL LOSSES. RECOMMENDATIONS EMPHASIZE THAT MAXIMUM EFFICIENCY OF ALL EQUIPMENT MUST BE MAINTAINED, RECORDS OF MONTHLY ENERGY USAGE MUST BE KEPT, AND ALL SYSTEMS MUST BE MONITORED REGULARLY. THE MANUAL ALSO DETAILS THE HEATING, COOLING AND REFRIGERATION, LIGHTING, AND DOMESTIC HOT WATER SYSTEMS. CASE HISTORIES PROVIDE EXAMPLES OF SUCCESSFUL ENERGY REDUCTION THAT INVOLVES NO DISCOMFORT OR SACRIFICE. COST BENEFIT STUDIES REPORTED HERE SHOW ENERGY AND OPERATING COST SAVINGS OF 15 TO 30 PERCENT BASED ON PRESENT FUEL COSTS. CHARTS, GRAPHS, AND TABLES ARE INCLUDED. COST INDEXES, AN ENERGY CONSERVATION EXAMPLE, AN ANALYSIS OF ENERGY SAVINGS, A BIBLIOGRAPHY, A GLOSSARY, ABBREVIATIONS, AND AN INDEX ARE APPENDED. (MRK)