Oil and gas discoveries in developing countries are often associated with short-sighted economic policies and, in response, calls to insulate resource management from populist impulses. We report on a randomized experiment testing methods to overcome this apparent tension between sound resource governance and democratic politics. Soon after Tanzania’s discovery of major natural gas reserves, we invited a nationally representative sample of voters to an intensive public deliberation of policy options featuring nationally recognized experts and small-group discussions. Democratic deliberation reinforced the public’s strong preference for rapid spending of gas revenues, but also increased support for various prudential and economically orthodox measures, including independent oversight of gas revenues, limits on government borrowing, and selling gas abroad rather than subsidizing fuel at home. These effects were driven by deliberation per se, rather than a pure information treatment, and show no evidence of contamination by facilitator- or peer-effects in group deliberations.