Street installations are a growing trend within the "street art" movement. Whereas conventional street art/graffiti is done on surfaces/walls "street installations" use 3-D objects/space to enhance/interact/interfere with the urban environment. Like graffiti, it is non-permission based and once the object/sculpture is installed it is left there by the artist. Street Installations are sometimes designed to be taken/moved by the public as part of interactive and ongoing "life" of the art work. Unlike graffiti, street installations are generally designed in such a way that no damage is done to the property or location in which the installation is placed.