Few policies are as universally accepted as raising primary school enrollment in developing countries, but the policy levers for achieving this goal are not straight forward. This paper merges household survey data with detailed school supply characteristics from official sources, in order to estimate the relative impact of demand and supply-side determinants of rural primary school enrollment in Mozambique. Policy simulations based on a set of “plausible” interventions show that demand-side interventions, particularly those aimed at raising rural adult literacy, will have the biggest impact on primary school enrollment rates.