Marriage in the Vaupés is a kind of movement: People, goods, and intangible commodities such as prestige follow marital paths linking families and settlements. It is thus not surprising that Tukanoans spend a great deal of time and energy negotiating marriages and observing and discussing how similar negotiations progress in other households.

Probably low population density, dispersed settlement pattern, egalitarianism, and a swidden horticultural base with a strong overlay of hunting, fishing, and gathering are the most important reasons why so much extralocal economic interaction is linked to affinal relationships. A strong component of the economic system is that people meet the demand for nonlocal goods and services by depending on their network of ties to other people and settlements through organized marriage exchanges rather than through direct commodity exchanges. This economic system suits an environment and level of technology requiring both extensive lands that must lie fallow for longer than they are cultivated and controls on overexploitation of hunting, fishing, and gathering resources. An evenhanded and flexible economic system involving a strong element of generalized reciprocity and little capital or stored surplus is necessary. A marriage system that allows for continual adjustments to the ecosystem and fosters some economic dependence on social relationships maintained through affinal links in a number of other settlements fits in well with this setting, for it places the most emphasis on exchanges of personnel rather than on exchanges of goods.