The book examines the artistic practice of the collective Tercerunquinto over the last two decades. Formed in the late 20th century in Monterrey, Mexico and integrated by Gabriel Cázares and Rolando Flores, and until 2014 by Julio Castro; the artists have made visible the informal architecture and the uses of unstructured urban borders related to the contemporary megalopolis. The association of the space with the architectonic precariousness, the frailty of its components, and the lack of public services are a central part of the discourses presented here: making visible a critical history of the urban outskirts. Tercerunquintoœs work is situated primordially at the conjunction of the structural, constructive and social values of grayʺ work (the architectural term when a construction begins to take the form we imagine at the beginning of the project. The enclosure walls rise, as do the walls of the house; in some cases, roof tiles or waterproofing are added. Also, internal pipes, wiring and utility connections are finished installing).The way the collective treats the space and institutions subject to their intervention certainly has immediate affinity with the undefined condition of the state in which the buildings of peripheral poverty are found.ʺ--Page 172.