This chapter discusses the institutional set-up of the AUBP, both as formally foreseen in its foundational documents and as it has evolved in practice since 2007. Building on the institutional framework of the African Peace and Security Architecture (APSA), it studies the key stakeholders and their respective roles within the programme, namely the AU Commission as coordinator at the continental level, the Regional Economic Communities (RECs) at the regional level, AU member states at the national as well as border communities at the sub-national level. Specifically, the chapter focuses on the day-to-day interactions, entanglements and friction between these different actors whose priorities, interests, perspectives as well as spatial imaginations concerning African boundaries diverge. It describes the paradigmatic differences regarding what the AUBP should achieve and how this should be done which pierce through in the everyday inner workings of the AUBP and highlights the constant renegotiations and morphing of the relations and hierarchies between these stakeholders within the “AUBP web”.