81 Fig. 1 - Trenado, T. (Ed): NO Signs. Un ensayo foto- gráfco sobre el impacto de las señales de de restricción y prohibición (NO Signs. A Photo-Graphic Essay on the Impact of Restriction and Prohibition Street Signs), 2015 The present working paper picks up from a project led by Toño Trenado in 2015 as part of his Master´s thesis on Art Books Publishing. The project consisted of the production of a book entitled NO Signs. A Photo-Graphic Essay on the Impact of Restriction and Prohibition Street Signs, and it was composed of photographs of street signs and public posters that included a negative order (“NO”/DON´T). Along with the photographs, there were three essays that addressed the nature of the mentioned written message from diferent perspectives. As an art historian, I worked on the aesthetic side of these public writings as well as their function and reception in the city space («Señales del NO en el espacio urbano: estrategias de prohibición y tácticas creativas de resistencia», «NO Signs in urban space: strategies of prohibition and creative tactics of resistance»). A few book samples were fnished but the project was never brought to market nor was it distributed in any way since the texts arrived only into the hands of the four co-authors. This paper aims to be a review, extension and continuation of the text that was once part of this unreleased book. Most of the photographs were taken in Madrid, Paris, Lisbon With, On and Against Street Signs On Art Made out of Street Signs Mª Isabel Carrasco Castro Marist College Madrid Program C/ Madrid, s/n Ofce: 9.0.40 Universidad Carlos III de Madrid, Getafe, Spain isabelakis@yahoo.es Abstract In The Practice of Everyday Life (1980), Michel de Certeau suggests the idea of a city in which there are, on one side, strategies of information, surveillance, control and infrastructure design laid out by the system and, on the other one, tactics defning the how-to-do of the users with regards to that system, that is, the operations by which they adapt them to align their own interests and needs. The texts allows us to examine the interventions of urban artists as a tactic characterized, as defned by De Certeau, as the harnessing of the system's resources (making do). This is more specifcally translated into adaptability, development on a space they do not own, identifcation and utilization of the occasion (time) and the inventiveness of diverting time and resources (shortcut and la perruque). In this work, we will take trafc signs of restriction and prohibition as one of the urban components that highlight the normativization of public spaces through the direct message of "NO" (not doing). Many artists have, in previous years, developed an interest in the artistic and symbolic possibilities of these signs and have developed works (tactics) as their response to them. Dan Witz (Chicago, 1957), Clet (Bretagne, 1966), Brad Dowey (Louisville, 1980) or DosJotas (Madrid, 1982) are good examples of this. Key words: De Certeau, strategies, tactics, street signs, Dan Witz, Clet, Brad Dowley, DosJotas Changing times: Tactics SAUC - Journal V4 - N1