The development of utility rates has been greatly aided by the progress that has been made in the computer industry. Spreadsheet programs, whether established on a microcomputer or on a larger system, are ideally suited for the manipulation and analysis of the large quantities of data associated with rate development. This chapter discusses the use of computer systems to design and analyze potential utility rate methodologies. The primary focus will be on the use of microcomputers and spreadsheet applications to develop rates. Some attention will also be given to larger systems using either other spreadsheets or specific programs written with a programming language such as Fortran or Pascal. Two software approaches are discussed in this chapter. The first is the use of spreadsheet software such as Lotus 1-2-3, Supercalc, and many others. The second approach is using a programming language to create a model specifically for utility rate analysis.