Choosing a spouse has always been an event subjected to strong social control. Consideration of socioprofessional elements is therefore necessary for an in-depth understanding of the microevolutionary consequences of marriage. Thus in this paper I explore the extent and causes of reproduction isolation between different socioprofessional groups of a 19th-century Italian community, Casalguidi. Various features of mate choice pattern were investigated by means of individual-level data. The results show that Casalguidi was a community with strong socioeconomic internal boundaries, in which social belonging mattered much more than geographic provenience. The bourgeoisie showed such a high degree of social homogamy that it was almost reproductively isolated. Much more openness and less isolation was found between the two categories of farm laborers and sharecroppers, and day laborers.