Building a capable public service is a key component of post-conflict state building. An effective public service is fundamental to the regulation of society, to managing public funds, and to service delivery. Yet in post-conflict environments, there is typically a tradeoff between the long-term objective of state building and securing the peace in the short term. To buy peace, political elites hand out public jobs and resources to constituents regardless of merit. Donors frequently rely on "parallel" project delivery structures rather than public servants to address citizens' pressing service delivery needs. Both of these practices may achieve short-term objectives but undermine state building. In the face of these trade-offs, how can capable public services be built in post-conflict societies? This paper aims to summarize the evidence base regarding this question. It does so by reviewing the evidence from post-conflict settings, and by discussing the validity of findings on public service reform from non-conflict settings. Given the distinctive tradeoffs invoked by securing the peace, and limited prior research on post-conflict settings, this topic presents a wide-open research agenda.