Previous studies have indicated that noneconomic factors, such as convenience, quality, security, and prestige, are increasingly important in consumer purchasing decisions. However, analyses to date-including both econometric and engineering models--have not explicitly considered these noneconomic factors. Such analyses are thus no longer adequate tools for understanding consumer preference and choice. This is clearly the case in the area of energy end-use technology purchases, in which noneconomic considerations are often dominant. SRI International's (SRI's) study represents a pioneering effort to evaluate these noneconomic factors systematically and to quantify their effects on consumer purchasing decisions. Specifically, it uses SRI's Values and Lifestyles (VALS) system to develop a preliminary market assessment model for projecting consumer adoption of natural gas end-use technologies. In summarizing the SRI study, this paper describes the technology market assessment model and illustrates its application to one selected existing natural gas end-use technology. It thus demonstrates the methodology for using consumer values and lifestyles data to improve projections of consumer purchasing behavior.