Conservationists are increasingly interested in changing human behaviour. One understudied aspect of such interventions is information flow. Different patterns of interpersonal communication and social structures within communities influence the adoption of behavioural changes through social influence and social reinforcement. Understanding the structure of information flow in a group, using tools such as social network analysis, can therefore offer important insights for interventions. For example, communications may be targeted to highly connected opinion leaders to leverage their influence, or communication may be facilitated between distinct subgroups to promote peer learning. Incorporating these approaches into conservation interventions can promote more effective behaviour change. This review introduces conservation researchers and practitioners to key concepts underpinning information flows for interventions targeting networks of individuals. Social scientists have advanced understanding of complex contagions – how behaviours spread through social networks – rapidly in recent years, suggesting new approaches to promote widespread behavioural change.Social network analysis is a powerful tool for understanding the social structures that influence the spread of behavioural changes, and can be used to inform these interventions. For example, measures of centrality can be calculated to identify key individuals, or community detection algorithms used to delineate socially important subgroups.Some interventional approaches are already being adopted in conservation, such as targeting influential opinion leaders, but further integrating understanding of information flows and social structures will make conservation behaviour-change interventions more effective, such as by targeting incubator neighbourhoods to initiate behavioural diffusion, or connecting subgroups for collective action.