Left-libertarianism (or left-wing libertarianism) names several related but distinct approaches to political and social theory, which stresses both individual freedom and social equality. In its classical usage, left-libertarianism is a synonym for anti-authoritarian varieties of left-wing politics, i.e. libertarian socialism, which includes anarchism and libertarian Marxism.Left-libertarianism can also refer to non-anarchist and non-Marxist political positions associated with academic philosophers Hillel Steiner, Philippe Van Parijs, and Peter Vallentyne that combine self-ownership with an egalitarian approach to natural resources. Left-libertarians, while maintaining full respect for personal property, are skeptical of or fully against private property, arguing that neither claiming nor mixing one's labor with natural resources is enough to generate full private property rights, and maintain that natural resources (land, oil, gold, vegetation) should be held in an egalitarian manner, either unowned or owned collectively. Those left-libertarians who support private property do so under the condition that recompense is offered to the local community.
Many left-libertarian schools of thought are communist, advocating the eventual replacement of money with labor vouchers or decentralized planning. On the other hand, left-wing market anarchism, which includes Pierre-Joseph Proudhon's mutualism and Samuel Edward Konkin III's agorism, appeals to left-wing concerns such as egalitarianism, gender and sexuality, class, immigration, and environmentalism within the paradigm of a socialist free market.