Contemporary diplomacy is subject to the same pressures of globalization as many other communication industries. However, insights from different areas of Media and Communication Studies have only been partly explored in the context of diplomacy. This article applies theories of transmedia storytelling, transmedia engagement and surveillance upon a case study of the recent Campaign to End Sexual Violence in Conflict. The aim is to investigate the ways in which contemporary diplomatic advocacy campaigns cope with fundamental problems such as media repertoires, co-created content, collective intelligence, digital convergence and stakeholder management. The article contends that co-creation and co-option of shared values through transmedia engagement techniques perform a disciplining role for stakeholders that may be linked to theories of surveillance and biopolitics. This study will be of much relevance to those interested in the significance of participatory culture theories to contemporary international advocacy, including its policies, strategies and mediating practices.