It is shown how to reduce computer usage significantly by building performance into the code. Compiler performance is first defined, and three Cobol environments chosen to illustrate compiler performance in various settings are described: two mainframes and one personal computer. The usage clause, data fields, data-type conversions, tables, file-blocking efficiencies, 'perform' and 'call' overhead, sorting efficiency, ISAM file performance, and compiler options are discussed. Ten steps to improve program performance in an organization's installation are recommended.<>