This article investigates structural change in Argentina between 1935 and 1960, a period of rapid industrialization and of relative decline of the agricultural sector. We use a dynamic three-sector computable general equilibrium model of the period to analyze the effects of the policies of import-substituting industrialization (ISI), and changing factor endowments, on the structure of the economy. We find that the declining land-labor ratio was more important than ISI in explaining relative stagnation in agriculture. ISI gave a substantial boost to manufacturing, but primarily at the expense of non-traded services, rather than of agriculture.