Raul Prebisch and Andre Gunder Frank developed dependency theory which argues that poorer countries' economies are negatively impacted by their relationships with richer countries. Dependency theory states that the wealth of rich nations increases at the expense of poor nations, as poor countries export raw materials to rich countries who manufacture goods and sell them back at higher prices. This creates underdevelopment in poor countries and enriches elites in both rich and poor countries who benefit from the unequal system. Dependency theory critics argue poor countries' internal markets cannot support industrialization and they lack political will and control over external forces to transform their economies. The document discusses dependency theory and provides context on its proponents and implications for development policies.