This chapter establishes the theoretical orientation of the study. Traditional IR approaches to regime development – which have typically drawn on a single research tradition – are mapped, and then contrasted with the pluralist approach taken in Negotiating Civil War, highlighting the rationale, principal benefits and challenges of drawing variously on Realist, Rationalist, Liberal and Constructivist insights. The hypotheses to be tested in each of the subsequent case studies chapters are then set out and their underlying explanatory factors identified. The chapter then sets out the potential interaction amongst these hypothesised factors in a ‘straw person’ diagram. The chapter concludes with a brief discussion of the key methodological considerations informing the study.