This study uses the correspondence among local inquisition tribunals in early modern Italy to understand how collegial networks shaped the activities of these inquisitions and their relationships with the ecclesiastical hierarchy that oversaw them. A substantial cache of mid seventeenth-century correspondence between the Inquisition of Venice and its outer tribunals on the Venetian mainland and elsewhere reveals the concerns of local inquisitorial officials and the strategies they used to navigate the practical, legal and political difficulties that threatened to wreck their prosecutions. The letters also demonstrate that the professional networks that inquisition officials cultivated in order to carry out their investigations were also personal. Along with requests for arrests and evidence, the clerics exchanged news, gossip and gifts and sought their colleagues’ assistance in advancing their careers and the interests of their clients. Finally, the correspondence shows the efforts of local officials to manage their relationships with the Roman officials that oversaw their tribunals. In effect, the outer peripheral tribunals of the Roman Inquisition were neither entirely local nor entirely Roman as they depended on each other for their operations and for reconciling local exigencies with the desires of the Church hierarchy in Rome.