The collaboration between university and industry under the institutional arrangement of the University Third Mission has been widely investigated by scholars and, more recently, with an increasing focus on the importance of trust. In this line of research, based on the study of six cases of collaboration in one of the more economically developed regions of Italy, this article aims at analysing how trust is produced -- or constructed -- by actors involved in the collaborative relationships to identify different processes, factors, dynamics by which such a construction takes place, shape and content, and to discuss its contribution to the rise and maintenance of such collaborations.