The current article considers the importance of the links existing between social relations and relations of trust, on the one hand, and economic and business relations on the other, in networks of firms, particularly networks of small firms that have formed involuntarily. Among these links, it is important to discover the way tacit and explicit information flows are established within the network and the conditions for them to occur. We examine these questions in a network of firms from the shoe industry using the methods and concepts of social network analysis. With this in mind, we have analysed the complex network of small firms by breaking it down into subnetworks in order to better understand its general structure. Our findings show that economic relations (cooperation, commercial exchanges) and social relations (trust, friendship, kinship, information interchanges) between the firms in the network are embedded within each other. The firms of the network exchange tacit information only with those firms with which they maintain stronger social and business links. Information and knowledge are treated as a strategic resource that is only shared with those companies that are not direct competitors.