This project will examine how people make decisions about appliance purchases and the effect that these choices have on energy demand. Currently, approximately half of U.S. greenhouse gas emissions are attributable to residential appliance use. However, consumers can reduce their long-run energy needs by replacing old appliances with ones that are more energy efficient. It is not surprising, then, that efficiency standards have been the cornerstone of U.S. energy conservation efforts to date. Unfortunately, the effect of these standards on appliance purchase behavior is not well understood. There are two primary reasons why. Current datasets lack crucial information, and even with appropriate data it is difficult to accurately model the dynamic aspect of appliance purchase behavior. This project addresses both of these issues.