This paper discusses the economic approach to the question whether there should be a legal duty to rescue and a corresponding liability for omissions. It discusses the law and economics literature which holds that a rule of no-liability for rescue is efficient since a legal duty to rescue may crowd out altruism and could create a substitution effect. The subsequent literature has refined and criticised this hypothesis, arguing that in particular cases, where a special relationship between the potential rescuer and the injurer or victim exists, a duty to rescue may be efficient. Empirical studies concerning the duty to rescue are also discussed, showing that notwithstanding the absence of a legal duty to rescue, rescue without law seems to be the norm in the us. Finally, the possibility of a duty to rescue in criminal law is discussed.