The Great Leap Forward disaster, characterized by a collapse in grain production and a widespread famine in China between 1959 and 1961, is found attributable to a systemic failure in central planning. Wishfully expecting a great leap in agricultural productivity from collectivization, the Chinese government accelerated its aggressive industrialization timetable. Grain output fell sharply as the government diverted agricultural resources to industry and imposed an excessive grain procurement burden on peasants, leaving them with insufficient calories to sustain labor productivity. Our analysis shows that 61 percent of the decline in output is attributable to the policies of resource diversion and excessive procurement.