This monograph is concerned with the determination of the allowed rate ofreturn in rate cases which, in part, determines the rates ofcharge to customers of public utilities. Rate of return determination has been a central topic in utility regulation for a century. Recent changes in the traditionally regulated markets - electricity, gas, and telephone - have shoved discussion of rate of return determination into the background, replacing it by technology changes, competition, downsizing, deregulation, and reg'ulatory incentive systems. These new issues have made the regula- tory sector, which...