ABSTRACT
It is axomatic that a system cannot be managed unless it is measured and that the measurements occur in a rigorous, defendable manner covering relevant spatial and temporal scales. Furthermore, it is not possible to predict the future direction of a system unless any predictive approach or model is supported by empirical evidence from monitoring. The marine system is no different from any other system in these regards. This review indicates the nature and topics of marine monitoring, its constraints in times of economic austerity, the sequence of topics subject to monitoring and the amount of monitoring of various topics carried out as indicated by the number of publications and researchers. We discuss the way in which the nature of monitoring is decided and we use examples to comment on the way monitoring leads to and responds to marine management and governance.