South Sudan’s rulers keep a tight grip on its oil wealth, blocking outside scrutiny and obstructing reforms urgently needed to ease both popular hardships and political tensions. Along with International Monetary Fund support, a peace deal has kickstarted new efforts to fix the country’s broken finances. South Sudan’s five-year civil war killed up to 400,000 people and brought the young nation close to collapse. If President Salva Kiir’s government begins to clean up the country’s budget, as it has pledged to do, opponents will have fewer incentives to take up arms again. Reform-minded South Sudanese and their external partners should focus on making the oil economy more transparent and account able by ensuring that revenue deposits go in a single public account and through other anti-corruption measures. Donors should press commercial lenders to disclose their payments to Juba and follow South Sudanese law.