Our paper addresses two gaps in the literature on management control mechanisms in the context of inter-organizational relationships. Firstly, several studies have focused on one-to-one relationships, but few take a network perspective which analyses the deployment of management control mechanisms in the context of networks involving multiple interactions between organizations. Secondly, even fewer studies have specifically tackled the use of these mechanisms in the context of mixed-type networks, where a public organization acts as the network coordinator responsible for key governance activities. This is the position in Ports, which are collectives of several related organizations and in which one organization - the " port authority" - assumes the role of network coordinator. In this paper we report the results of a case study, the aims of which were: to identify the management control mechanisms deployed, or relied upon, by the Portuguese Port Authority in the Port of Aveiro in the exercise of its coordinating role; and to discern - on the basis of theoretical reasoning and empirical evidence - the factors explaining the nature and use of these mechanisms.Several conclusions emerged from the study. A general conclusion was that our prior literature-based theorization is generally consistent with the case observations. That is, in mixed-type networks, the nature and use of management control mechanisms by the public organization acting as a network coordinator seems to be shaped by its assessment of motivations to cooperate and of the contribution to network performance of the various organizations involved in the network. Other more specific conclusions are encapsulated in a " coordination framework" , which relates those assessments to specific features of the management control mechanisms. Crucially, our results provide insights into the roles of public organizations acting as network coordinators in the context of mixed-type networks, and, in general, on the nature of the numerous such public organizations in today's economy and society.