The main challenges in international health are to scale up effective health interventions in low- and middle-income countries in order to reach a higher proportion of the population. This can be achieved through better insight into how health systems are structured. Social network analysis can provide an appropriate and innovative paradigm for the health systems researcher, allow new analyses of the structure of health systems, and facilitate understanding of the role of stakeholders within a health system. The social network analysis methodology adapted to health systems research and described in detail by the authors comprises three main stages: (i) describing the set of actors and members of the network; (ii) characterizing the relationships between actors; and (iii) analysing the structure of the systems. Evidence generated through social network analysis could help policy makers to understand how health systems react over time and to better adjust health programmes and innovations to the capacities of health systems in low- and middle-income countries to achieve universal coverage.