This is a beautiful little statement that captures why I believe “libertarian socialism,” far from being self-contradictory, is in fact the only non-contradictory form of both libertarianism and socialism:
To be a true libertarian requires you to support workers’ control otherwise you support authoritarian social relationships. To support workers’ control, by necessity, means that you must ensure that the producers own (and so control) the means of producing and distributing the goods they create (i.e. they must own/control what they use to produce goods). Without ownership, they cannot truly control their own activity or the product of their labour. The situation where workers possess the means of producing and distributing goods is socialism. Thus to be a true libertarian requires you to be a socialist.
Similarly, a true socialist must also support individual liberty of thought and action, otherwise the producers “possess” the means of production and distribution in name only. If the state owns the means of life, then the producers do not and so are in no position to manage their own activity. As the experience of Russia under Lenin shows, state ownership soon produces state control and the creation of a bureaucratic class which exploits and oppresses the workers even more so than their old bosses. Since it is an essential principle of socialism that inequalities between people must be abolished in order to ensure liberty, it makes no sense for a genuine socialist to support any institution based on inequalities of power… The state is just such an institution. To oppose inequality and not extend that opposition to inequalities in power, especially political power, suggests a lack of clear thinking. Thus to be a true socialist requires you to be a libertarian, to be for individual liberty and opposed to inequalities of power which restrict that liberty.
from An Anarchist FAQ