Headhunting practice has been the subject of intense study to assess and interpret its social roles, functions, and motivations. Themes include mortification of the rival, ritual violence, cosmological balance, the display of manhood, cannibalism, dominance over the body and soul of his enemies in life and afterlife, as a trophy and proof of killing, show of greatness, prestige by taking on a rival's spirit and power, and as a means of securing the services of the victim as a slave in the afterlife.

The primary function is ritual and ceremonial. It is part of the process of structuring, reinforcing, and defending hierarchical relationships between communities and individuals.

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