Assessing the economic development of Latin America during the twentieth century requires reliable estimates of living standards, as measured by per capita income, life expectancy, and literacy. New comparable series for Latin America suggest that these three indicators made the greatest strides during the period from 1940-80. This progress is probably related to state-led industrialisation, improvements in public health, and urbanisation. Comparison with US levels reveals that, while average per capita income has generally remained steady, relative living standards (measured by a composite welfare index) have risen gradually as life expectancy in the two regions has converged