This is an introduction to the thought of the radical French thinker Félix Guattari. Guattari's main works were published in the 1970s and 1980s. His background was in psychoanalysis -- he was trained by Lacan and he practised as a psychoanalyst for much of his life. He developed a distinctive psychoanalytic method informed always by his revolutionary politics. Guattari was actively involved in numerous political movements, from Trotskyism to Autonomism, tackling ecological and sexual politics along the way. A true believer in collectivity, much of his work was written in collaboration, most famously with Gilles Deleuze. This is also an introduction to key concepts such as schizoanalysis, transversality, a-signifying semiotics and various kinds of machine.