Super-exploitation is one of the key Marxist concepts, developed by Marxist dependency theorists, of the impact of imperialism on nations and regions of 'the periphery', also widely categorised as the 'Global South' in contrast to the Imperialist 'core' or metropolitan countries in which Capital historically accumulates. Unequal exchange between countries and regions is another concept to which is attributed the actualising of the continuing wealth transfer from periphery to core, and is frequently linked in the associated theoretical discussions.