Self-sustainability and self-sufficiency are overlapping states of being in which a person or organization needs little or no help from, or interaction with, others. Self-sufficiency entails the self being enough (to fulfill needs), and a self-sustaining entity can maintain self-sufficiency indefinitely. These states represent types of personal or collective autonomy.[1] A self-sufficient economy is one that requires little or no trade with the outside world and is called an autarky.