I argue in this chapter that the negotiations surrounding both the Geneva Conventions and the Protocols Additional to the Geneva Conventions demonstrate that the expectation of reciprocity still exists within IHL, despite significant concessions towards humanitarianism. This chapter proceeds in four parts. In the first section, I give a brief history of IHL and highlight the role historically played by expectations of reciprocity within the regime. In sections two, three and four I examine the negotiations that took place at the Diplomatic Conferences of 1949 and 1974–7 that updated Geneva law. Each section demonstrates how, despite the willingness of states to extend the protections of IHL regulations to more armed conflicts and individuals, they were only willing to do so given the expectation of a reciprocal commitment – both de jure and de facto – to comply with the law. I conclude with some remarks about what the history of these negotiations demonstrates about the continued role played by expectations of reciprocity in the POW regime, given that this is the central focus of the subsequent two chapters.