As several authors have shown, culture is becoming a key tool of the urban planning kit. It is used by urban decision-makers to create symbolic and economic values, which are often considered as a competitive advantage for cities. Nevertheless, when so many cities are using the same strategies, to what extent does culture-led planning allow a city to distinguish itself? Here, we ask whether alternative cultures can lead to an urban resistance against these sanitised and homogenised cityscapes. Alternative cultures provide both cultural spaces and unique urban experiences, but can also give a place a new type of symbolic value. How can these alternative cultures be used by planners to pioneer urban regeneration projects? How are they influenced by cultural policies? Are they attracting other urbanites, such as the gentrification theories argue, or do they reveal a large diffusion of conditions of works and constraints in everyday life? Based on several examples in Paris, this paper intends to show the shift in the attitude of planners and authorities toward what we call off cultural scenes. Increasingly, these decision-makers are accepting of and entering into discussions with off artists, using them as pioneers in urban developments and copying their approach in new cultural projects. Many of these changes illustrate the willingness of the current mayor of Paris to promote the city as a creative and open place to work, invest, create and live. Later, this paper will analyse these changes with respect to three case studies and address several questions: How does the presence of off artist spaces help to balance an overly sanitised urban project? What is the value of these off spaces to cultural planning? How do off spaces, such as artist squats, inspire new cultural policies? Do off cultural scenes promote or generate gentrification or, rather, reveal a global socio-economic trend which re-valorises inner-city locations? Finally, our work here leads to a reappraisal and serves as a reminder of the importance of serendipity in urban life and, thus, in urban planning.