The vitality and utility of a network are affected significantly by the network management system (NMS) that is used to administer and monitor the network. However, models that can characterize the quality of a NMS are generally missing in the literature. In this paper, we introduce the concept of quality of monitoring (QoM), provide a mathematical formulation based on stochastic processes that can be used to model a network monitoring system and define QoM metrics based on this formulation. A formal analysis of the proposed framework along various metrics is also provided, along with a case study of its application to network monitoring in a mobile ad hoc network. © The Author 2009.