This article is focused on the hypotheses of Raúl Prebisch and Hans Singer regarding the centre-periphery model, which is the cornerstone of development theory for peripheral countries. The article emphasizes aspects of theory and policy related to the political economy of the Economic Commission for Latin America and the Caribbean (ECLAC) from the early 1950s to the present. It shows how, since the 1980s, ECLAC economists —influenced by evolving neo-Schumpeterian models and equipped with sophisticated microeconomic instruments— have undertaken a critical appraisal of the import substitution model in Latin America while retaining Raúl Prebisch’s original hypotheses on the external forces restricting the economic development of peripheral countries.