Voluntary slavery (or self-sale) is the condition of slavery entered into at a point of voluntary consent. In ancient times, this was a common way for impoverished people to provide subsistence for themselves or their family and provision was made for this in law. For example, the code of Hammurabi stated that "besides being able to borrow on personal security, an individual might sell himself or a family member into slavery". In medieval Russia, self-sale was the main source of slaves.
In ancient times, one of the most direct ways to become a Roman or Greek citizen was by means of a self-sale contract. The laws surrounding Roman and Greek manumission made it quite possible for such erstwhile slaves to then become citizens or near-citizens themselves.
Jean-Jacques Rousseau contends that in a contract of self-enslavement, there is no mutuality. The slave loses all. The contract negates his interests and his rights. It is entirely to his disadvantage. Since the slave loses his status as a moral agent once the slave contract is enforced, the slave cannot act to enforce anything owed to him by his master. Rousseau contrasted this to the social contract, in that the subjects of the government have control over their masters.John Stuart Mill wrote a critique of voluntary slavery as a criticism of paternalism.
The term voluntary slavery is often used in polemical writings and rhetoric on a range of subjects. It has been asserted, for instance, that the capitalist wage system amounts to voluntary slavery and is contrary to human dignity and inalienable human rights. Libertarian Murray Rothbard criticized the term as self-contradictory.