During the July Monarchy, De Foy’s matrimonial agency was flourishing. This article uses three of De Foy’s ledgers located at the Archives de Paris to investigate the development of new matchmaking practices. The marriage agency sold access to unsuspecting young women from good families to young men who were eager to integrate themselves into Parisian society. De Foy mobilized a large, elaborate network of informants and contacts for this purpose. Revealing the inner workings of the obscure matchmaking industry, this article examines the history of marriage choice in a city experiencing tremendous change. During a period when the bourgeoisie worked to consolidate the private sphere, the marriage agency assumed the important function of providing social mobility to its clients.