This paper investigates preference heterogeneity of wine consumers by using latent class models based on attitudinal questions. Such responses turn out to be an important source of additional information when the goal is to identify different groups of people with a similar wine preference structure. We assume that preferences are latent and the responses to attitudinal questions are the visible effect of this latent heterogeneity. We find evidence of 4 different classes of respondents with similar response patterns. We focus on preferences for a well-known wine, the Prosecco, and sample the population in the area of production. For each preference-class we estimate a class-specific WTP equation for this wine, so as to estimate the class responsiveness of WTP to various determinants. Estimates for a 4-class model are discussed in detail to illustrate the potential of this approach in characterizing the preferences of local consumers for the two most common certifications of origin.