Self-governance, self-government, or self-rule is the ability of a person or group to exercise all necessary functions of regulation without intervention from an external authority. It may refer to personal conduct or to any form of institution, such as family units, social groups, affinity groups, legal bodies, industry bodies, religions, and political entities of various degree. Self-governance is closely related to various philosophical and socio-political concepts such as autonomy, independence, self-control, self-discipline, and sovereignty.

In the context of nation states, self-governance is called national sovereignty which is an important concept in international law. In the context of administrative division, a self-governing territory is called an autonomous region. Self-governance is also associated with political contexts in which a population or demographic becomes independent from colonial rule, absolute government, absolute monarchy, or any government that they perceive does not adequately represent them. It is therefore a fundamental tenet of many democracies, republics and nationalist governments. Mohandas Gandhi's term "swaraj" is a branch of this self-rule ideology. Henry David Thoreau was a major proponent of self-rule in lieu of immoral governments.