"Psychogeography is the study of the effects of geographical settings, consciously managed or not, acting directly on the mood and behaviour of the individual".

Psychogeography research is carried through non-scientific methods such as the derive, aimless drifting through the city, trying to record the emotions given by a particular place; and mental mapping, the production of mood-based maps.

Psychogeography was developed as a critique of urbanism by the Lettrist International and then by Situationist International in the late fifties. Today, it is pursued by artists, radical thinkers and, on an academic level, geography researchers.

The situationists developed an armoury of confusing weapons intended constantly to provoke critical notice of the totality of lived experience and reverse the stultifying passivity of the spectacle.

An example of a situation-creating technique is the dérive. The dérive is the first step toward an urban praxis. It's a stroll through the city by several people who are out to understand the "psychogeographical articulation of the modern city". The strollers attempt an interpretive reading of the city, an architectural understanding. They look at the city as a special instance of repressed desires. At the same time, they engage in "playful reconstructive behavior". Together they turn the city around. They see in the city unifying and empowering possibilities in place of the present fragmentation and pacification.

One of psychogeography's principle means was the dérive. Long a favorite practice of the dadaists, who organized a variety of expeditions, and the surrealists, for whom the geographical form of automatism was an instructive pleasure, the dérive, or drift, was defined by the situationists as the 'technique of locomotion without a goal', in which 'one or more persons during a certain period drop their usual motives for movement and action, their relations, their work and leisure activities, and let themselves be drawn by the attractions of the terrain and the encounters they find there'. The dérive acted as something of a model for the 'playful creation' of all human relationships.

Unlike surrealist automatism, the dérive was not a matter of surrendering to the dictates of an unconscious mind or irrational force. Indeed, the situationists' criticisms of surrealism concluded that 'the unconscious imagination is poor, that automatic writing is monotonous, that the whole genre of ostentatious surrealist "weirdness" has ceased to be very surprising'. Nor was everything subordinated to the sovereignty of choice: to dérive was to notice the way in which certain areas, streets, or buildings resonate with states of mind, inclinations, and desires, and to seek out reasons for movement other than those for which an environment was designed. It was very much a matter of using an environment for one's own ends, seeking not only the marvelous beloved by surrealism but bringing an inverted perspective to bear on the entirety of the spectacular world.

This "turning around" or détournment is a key strategic concept of the Situationists. Détournment is a dialectical tool. It is an "insurrectional style" by which a past form is used to show its own inherent untruth-- an untruth masked by ideology. It can be applied to billboards, to written texts, to films, to cartoons, etc., as well as to city spaces. Marx used it when he "turned Hegel on his head". He used the dialectic in the study of history to expose the ideological nature of Hegel's idealism. The Situationists use détournement to demonstrate the scandalous poverty of everyday life despite the plenty of commodities. They attempted to demonstrate the contrast between what life presently is and what it could be. They wanted to rupture the spell of the ideology of our commodified consumer society so that our repressed desires of a more authentic nature could come forward. The situation is based on liberated desires rather than alienated ones. What these desires are cannot be stated a priori. They will emerge in the revolutionary process of situation-creation, of détournment. Presumably, communality and public urban space will emerge as more desirable than commodification & fragmentation.