The characteristics of market-based economies may be enlightened by an analysis of economies that are not ‘fully’ market-based ones. A major question is the understanding of the determinants of the long-term economic stagnation of some of them, notably low-income countries. More specifically, a question is why, in contrast with industrialised economies, ‘commodification’ in these countries has not been associated with growth. It is argued that capitalism has fostered dynamics of commodification in these agricultural economies, which became economies based on primary ‘commodities’ – unprocessed commodities thus becoming ‘commodified’. Raw commodities are the principal source of wealth of most developing countries and are therefore public goods in the sense that they should not be viewed as commodities exclusively produced for markets. The export of commodities could have been the base of developmental public policies, e.g. industrialisation. Yet these dynamics have articulated with specific types of financing and specific institutions both at the global and domestic levels. This has induced cumulative causation processes where instabilities combine with power asymmetries, which have generated social costs and economic stagnation. The paper firstly analyses the transformation of these countries into ‘commodity-dependent’ poor economies: a key feature of primary commodities exchanged on international markets is the volatility of their prices, which has destabilising effects (terms-of-trade shocks, Dutch disease), and is compounded by the financialisation of commodity markets. The paper secondly shows that this transformation relies on the ‘externalisation’ of policies and financing, and fosters specific institutions. Commodity-dependence marketise poor economies’ societies into global volatile commodity and financial markets, which inherently constrain developmental public policies.< Réduire