Constriction is a method used by various snake species to kill their prey. The snake initially bites its prey and holds on, pulling the prey into its coils or, in the case of very large prey, pulling itself onto the prey. The snake will then wrap one or two coils around the prey, typically the prey's chest. Contrary to myth, the snake does not crush the prey, or even break its bones, but instead squeezes, tightening its grip every time the prey exhales and holding firm, until the prey can no longer draw in air. The prey asphyxiates, and the snake then begins to feed. The entire process is suprisingly rapid, with prey often succumbing as quickly as a minute after being struck.

Certain groups of snakes have sterotyped patterns of constriction, including the number of coils they use and the orientation of the coils. Also, there is controversy about how much role restriction of circulation plays in subduing prey.