Economic cost-effectiveness analysis is a systematic approach to assessing benefits and costs associated with different actions. This analysis, as applied to energy conservation programs, is complicated greatly by the existence of intangible benefits and costs. A further complication occurs when the input values are uncertain. Such inputs include the useful lives of measures installed, the appropriate discount rate, and the expected levels of savings. This paper shows how one can incorporate input uncertainty and some intangibles into the cost-effectiveness analysis calculations. The Hood River Conservation Experiment provides the framework for analyzing these issues and serves as a pilot program for future conservation implementation. Copyright 1990 Western Economic Association International.