This case outlines my experience of applying social network analysis to analyze a rather complex health systems topic (interactions between different health system actors). The case highlights the conceptual and methodological challenges that had to be considered in defining the communication relationships to be measured, designing the social network analysis questions, and collecting the social network analysis data in the field. Notwithstanding the challenges, this case highlights the utility of social network analysis as a method that can provide quantifiable measures of the extent to which interdependent actors communicate in a health system. I applied social network analysis to quantify, for the first time, communication interactions between two sets of actors in South Africa's health system: HIV program managers and general health service managers. In South Africa, HIV program and general health service managers are expected to perform differentiated but interdependent tasks to ensure the coordinated delivery of health services. Health policy in South Africa requires these managers to collaborate–given the interdependent nature of their tasks-but their relationships have historically been fraught with tensions. My research applied social network analysis to describe whether, and the extent to which, these managers communicate to provide an indication of whether the minimal level of collaboration is happening.