Chapter 1 introduces the argument, summarises the findings, and describes the conceptual framework applied throughout the book to analyse UN mediation as a gendered-colonial institution. It begins by noting the slow progress of the WPS Agenda in UN mediation, which the scholarly literature has not adequately addressed. It also stakes out the significance of WPS in UN mediation for the realisation of women's right to political participation, the advancement of gender equality in post-conflict contexts, and the diffusion of international approaches to gender-sensitive mediation from the UN to other organisations. The next section discusses how UN mediation can be analysed as an institution and identifies the key concepts and techniques used in parsing its gendered institutional logics. It also argues for using decolonial concepts of gender in studying the UN. Next, the chapter describes the interpretive research design and considers the ethical and practical implications of this approach. Last, the chapter concludes with an overview of each chapter.