Prospect wants originate upstream from the marketplace, in the context of everyday life and work. Researchers in marketing attempt to read wants by measuring and decomposing consumer preferences for marketplace offerings. In this paper, we show that consumer preference for offerings reflects an interaction between motivating conditions that prompt users to action, and capability of a brand's attributes to address the source of the motivation. A hierarchical Bayes conjoint model is proposed for measuring motivating wants that exist upstream from the marketplace and instrumental wants that are expressed as reactions to marketplace offerings. The model is illustrated with data from a national survey of the concerns and interests that prompt prospects to brush their teeth and their preference for toothpaste attributes .