The principal forms of economic organization outlined by Karl Polanyi (1957) - reciprocity, redistribution, and market forces - have been widely used in anthropological discussions of exchange. Paul Bohannan describes the relevance of these economic modes to exchange:

Reciprocity involves exchange of goods between people who are bound in non-market, non-hierarchical relationships to one another. The exchange does not create the relationship, but rather is part of the behavior that gives it context.

Redistribution is defined by Polanyi as a systematic movement of goods towards an administrative center and their reallotment by the authorities at the center.

Market Exchange is the exchange of goods at prices determined by the law of supply and demand. Its essence is free and casual contract (Bohannan 1965: 232).

In principle, the price-fixing aspect of market based exchange has an integrative effect and entails communication between segments of the exchange sphere. For the trader, market exchange involves risk and potential profit. For the producer, the consumption patterns and fluctuations in demand should be sensed all the way back in the contexts of production. Market articulation in land-locked regions of Asia and North Africa provided the initial contexts for large-scale caravans in the Old World. With caravans perennially under threat of robbery or obligation to pay duties for crossing sovereign land, the "nomadic empires of the Turk, Mongol, Arabic, and Berber peoples were spread out like nets alongside transcontinental caravan routes" (Polanyi 1975: 146-149). In contrast to market mechanisms, Polanyi also described exchange modes of institutional or administered trade, where material needs were satisfied through the movement of goods but the practice was not motivated by "profit" for merchants in the market sense of the term but rather to meet institutional goals (Salomon 1985: 516;Stanish 1992: 14;Valensi 1981: 5-6). In this type of trade, value and equivalencies are established by political authority or by precedent.