This briefing paper (2016) summarises shifts in international engagement in South Sudan from humanitarian aid to development and institution-building, and then back again to crisis response. This paper analyses why current aid frameworks have been mostly unsuccessful in their efforts to promote sustainable institutions and peace in South Sudan. The central argument is that aid actors largely failed because they applied technical solutions to political problems. What is needed is a rethink in approaches, modalities, and time frames, and better use of contextual and political analysis, in order to avoid similar failures in the future.