Security sector reform (SSR) in post-conflict environments encompasses a broad range of efforts to improve capacity, governance, performance, and sustainability. The fiscal implications of SSR decisions often are neglected, however. The negative consequences of this neglect include unsustainable reforms, the squeezing out of other vital sectors, and ultimately under-provision of security itself. This paper argues for a “right-financing” approach to SSR that strikes an appropriate balance between current needs and the goal of building a fiscally sustainable security sector. The paper offers four policy proposals: first, build fiscal dimensions of the security sector into peace agreements, post-conflict needs assessments, development strategies, and expenditure planning; second, align short-run policies with long-term budgetary realities; third, move to a “service-delivery” model based on provision of law-and-order and justice services to the citizens; and finally, strengthen international capacities to support these right-financing policies.