This study examines the strategies that guide the role of end-users in new product development (NPD) in UK consumer durable firms. NPD success factor literature identifies the involvement of the end-user and a focus on their needs as important contributors to product success. The predominantly scientific and industrial focus of these studies means that there is, however, little information on how companies in consumer markets involve users to achieve successful products. This study fills a gap by examining the role of product users in the development of successful consumer durable products in UK firms. The products were identified through the use of a success scale developed from Griffin and Page 1993, 1996, and the award of the Millennium Product marque. An inductive approach utilising both quantitative and qualitative methods was employed and the study identified discrete groups of users involved for specific purposes in the product development process. Two strategies were identified as guiding userinvolvement: in the Expediency strategy, employees or 'internal users' were involved for rapid testing of designs where speed-to-market was considered to be a key competitive factor. The Risk Reduction strategy involved both external and internal users when products were more complex and a focus on product quality and getting it 'right first time' were important. It was also found that the firms either developed products based on their own interpretation of the users' needs, 'consumer-driven', or driven by retailers' demands and suggestions, 'retailer-driven'. Following further testing with all sixty-five products, it was concluded that the perceived complexity of the product determined which strategy was chosen, and the level of market orientation in the firm established the driver. This thesis extends the NPD success-factor literature by establishing that the involvement of users is a contributor to successful consumer durable product development. It also identifies 'internal users' as a previously unrecognised group of users and relates the use of different groups of users to two distinct strategies. The Risk Reduction and Expediency strategies also extend the 'first-mover advantage' literature by concluding that products developed with the Risk Reduction Strategy were more successful than those that used an Expediency Strategy. Although these products were not usually first-to-market they benefited from being of superior quality.