Murray Bookchin was an American social theorist, author, orator, historian, and political philosopher. A pioneer in the environmental movement, Bookchin formulated and developed the theory of social ecology and urban planning within anarchist, libertarian socialist, and ecological thought. He was the author of two dozen books covering topics in politics, philosophy, history, urban affairs, and social ecology. Among the most important were Our Synthetic Environment (1962), Post-Scarcity Anarchism (1971), The Ecology of Freedom (1982) and Urbanization Without Cities (1987). In the late 1990s, he became disenchanted with what he saw as an increasingly apolitical "lifestylism" of the contemporary anarchist movement, stopped referring to himself as an anarchist, and founded his own libertarian socialist ideology called communalism, which seeks to reconcile Marxist and anarchist thought.