As human activities increasingly threaten the ecosystems on which they depend, one of the main questions our societies are facing is related to the resilience – seen as a necessary element of sustainability – of social–ecological systems (SESs). SESs are composed of many heterogeneous elements including human actors such as institutions and resource users, and natural components such as land patches, animal species, etc. The numerous relationships between these different entities shape complex, dynamic networks of social–ecological interdependencies. Once described as networks, SESs can be analysed using a variety of network metrics, which may potentially help to better quantify and evaluate the resilience of SESs to external or internal perturbations. In this paper, we provide a broad overview of the latest progress in network theory as applied to SESs and discuss how network metrics may be used to assess the sustainability of an SES.