Product testing has been a relatively neglected area in the literature of market research. This paper reviews current thinking and practice, discusses some major methodological issues and indicates some areas for further investigation. The first section looks at the basic assumptions of product testing methodology, including the nature of the respondent's task and the relationship between discrimination and preference. The second section uses the product life cycle analogy in considering the varied roles of product testing in the decision processes of marketing. Finally, the paper discusses a number of problem areas in product testing, presenting evidence for certain preferred methods and, in other cases, demonstrating the need to relate technique to marketing problem or product field.