Research evaluating such interventions tends to focus on measuring their impact on intended outcomes and, in some cases, on establishing whether exposure to the intervention follows a typical dose response curve. While this is important, there is a paucity of research into the more nuanced roles intervention and social network factors may play in achieving these outcomes, making it difficult to understand how different aspects of the intervention worked (or did not), and how it could be improved or best adapted in different contexts. For example, while a number of studies on the Stepping Stones HIV intervention found it to be effective, Bradley et al.’s  study on the diffusion of the intervention among social networks revealed important weaknesses. They observed that while Stepping Stones aims to have a community level effect, there was only diffusion of knowledge among personal contacts and limited community level diffusion. Examining diffusion provided key insights into how the intervention could further strengthen diffusion, increasing impact.