“Maybe the zone is a very complex system of tolls… I have no idea what goes on here in the absence of man. But as soon as someone arrives everything goes haywire… the zone is exactly how we created it ourselves, like the state of our spirits… but what is happening, that does not depend on the zone, that depends on us.” from Stalker, a movie by A. Tarkovskij from 1979.
Stalker, laboratorio d’arte urbana (urban art lab), is a collective based in Rome. 
Stalker proposes experimental strategies for intervention founded on exploratory spatial practices, using playful, convivial, and interactive tactics that relate to an environment, its inhabitants and their local culture.
Such practices and methods are conceived to catalyze and develop evolutionary and self-organizing processes through the social and environmental fabric specifically in the areas where through abandonment or impoverishment basic necessities are lacking. The traces of these interventions constitute a sensible mapping on the complexity and dynamics of the territory, realized through the collective contribution of individuals from different backgrounds and disciplines, who together investigate, document and participate in transformations taking place on the ground.
Stalker uses these strategies that employ direct unedited forms of cooperative documentation to contribute and promote among the local populations better self-awareness of their community and of their environment in order to enhance the quality of creative participatory feedback and improve and strengthen community methods for managing local territorial and urban problems.
I report here their manifesto:
• STALKER is a collective subject that engages research and actions within the landscape with particular attention to the areas around the city’s margins and forgotten urban space, and abandoned areas or regions under transformation. These investigations are conducted across several levels, around notions of practicality, representations and interventions on these spaces that are referred to here as “Actual Territories.” Stalker is together custodian, guide and artist for these “Actual Territories.” In the multiple roles we are disposed to confront at once the apparently unsolvable contradictions of salvaging through abandonment, of representation through sensorial perception, of intervening within the unstable and mutable conditions of these areas. 
• THE ACTUAL TERRITORIES constitute the built city’s negative, the interstitial and the marginal, spaces abandoned or in the process of transformation. These are the removed lieu de la memoirs, the unconscious becoming of the urban systems, the spaces of confrontation and contamination between the organic and the inorganic, between nature and artifice. Here the metabolization of humanity’s discarded scrap, or nature’s detritus, produces a new horizon of unexplored territories, mutant and by default virgin, that are for Stalker “Actual Territories.” The term “actual” indicates the process in which space comes into being. The “actual” is not what we are, but rather that we are becoming, that is to say the “other” that becomes other (Foucault). Such territories are difficult to render intelligible and therefore projectable, because they lack connections to the present and therefore are extraneous to contemporary language. Their conscious presence cannot come about by direct experience, they are to be physically witnessed rather then represented. The archive of experiences is the only form of mapping possible for these “Actual Territories.” 
• ENTERING THE TERRITORIES, perceiving the discarded territories, in completing such a route, between that which is secure, quotidian, and that which is uncertain, generates a sense of dislocation, a state of apprehension. This altered state induces a perceptual intensification unexpectedly giving the space a meaning, making “everywhere” a place for discovery, or instead a dreaded place for an undesirable encounter. The gaze becomes penetrating, the ear becomes keen to every sound.
• CROSSING THE TERRITORIES on foot establishes an unmediated experience, allowing for a more dynamic reading. A nomadic research, a mode of capturing the act of crossing without regimentation, ratification or definition of the object examined, so as not to prevent its becoming. Crossing is for Stalker a creative act, that means creating a system of relations within the chaotic juxtaposition of time and space that characterizes “Actual Territories.” Crossing means composing in a single conscious parcours the strident contradictions that animate these spaces, in a search for unedited harmony. Crossings and making crossings, inducing into the perception of the actual because it can become diffused into the general consciousness, while avoiding, however, banalizing its linguistic meaning.
• PERCEIVING THE BECOMING, intensifying perception, making one available to listen, is a necessary condition in order that the territories unveil themselves to those who desire crossing them. Making oneself available to perceive the unconscious language of mutation, opens an interrogation within the given pretense of describing and identifying. It stimulates an actual transcendence, in that of an inexhaustible perception of existing signifiers through continuous movement. It is the event that escapes without disappearing (Tiziana Villani) It is the objective in perceiving the scraps of atemporal spaces in a time continuum. It is the objective of signaling our contact¹s trace with that object and spectacle, in as much as it vibrates our gaze, our touch, our ears, our sense of risk, our sense of destiny. It is no longer about providing information but about depositing testimony. (Merleau Ponty). 
• FRACTILE ORGANIZATION. Stalker, confronted by the study of complex geometries, considers that the amount of marginal area in relation to an organism¹s surface is an index of its wealth, given that it is as much the articulation of voids, at diverse scales, that determines the very structure of an organism. The voids constitute that “background” on which to read the form of the city that would otherwise appear homogeneous, deprived of a complex evolutionary dynamic and therefore of life itself.
• CONTINUITY AND PENETRATION OF “ACTUAL TERRITORIES” THROUGH THE CITY. To defend the “Actual Territories,” to guarantee the maximum of continuity and of penetration within systems of urbanization, is to enrich and give life to the city through the continuous and diffused confrontation with the unknown. In this way it will be possible to recover within the profound heart of the city, the wild, the non-planned, the nomadic.
• THE ROUTE AS A COGNITIVE MAP. Stalker experiments on the urban agglomerate as if it were a grand cognitive map that is updated continuously through each crossing. The city’s stain-like shape finds analogies to representations of the human mind. The human mind is neither a unity, nor a structure organized according to a given hierarchy; it is an ensemble of separate capacities, frequently localized in specific regions of the brain (G. Jervis). It is interesting to observe how these images have in common a problem with the patterns of localization of different realities that live separately by different conditions, of which the links and the connections are created by routes. To gather these realties presupposes measuring oneself within a dynamic mode in movement. A movement capable of sectioning the design of this “landscape” in thousands of possible routes each of them different from another, without every passing through the center.
• THE ABANDONEMENT. The attempt at defining and controlling the entire territory, mirage of our western culture, just when it seemed most likely to realize itself, gives forth its first water. The first cracks have opened in the very hearts of our system: the large cities. The forest that at one time surrounded cities and villages, where bears and wolves, but also the nightmares would hide, where the fantasies and the very idea of liberty itself were shoved far from the city, put into the corners, restricted and in an unbelievable act of clemency, protected. And here it is now that that same forest rises again, exactly there in the cities where the territory’s systems of appropriation and control are most ancient and crumbling. Given the impossibility of total human control, the cement under which the forests were covered has cracked open, the earth flowers in new and unpredictable forms, preparing to contest with its human occupants the domination of space, from the scrap-heaps and beyond. To forecast the unforecastable, to save the coming into being of the “Actual Territories,” means to abandon them. For abandonment is the maximum form of a cure for that which has developed outside human will and plan.
• THE PROJECT. To intervene on a territory is not merely an act of planning but an act of creation, an attempt to assemble contradictions and transform them into poetic relationships: ultimately one is more attentive to modifying how space is perceived than the way space itself exists.