The relationship between cities and innovation in present times can be regarded from a distinctive perspective. As it is vital to rethink our development patterns, in order to contrast global warming and its ominous threats, cities are themselves concrete materials for innovation. Therefore, cities challenge the very same concept of innovation by adding the long-term perspective to its social assessment framework. Cities are therefore seen both as hotbeds of creativity and innovative culture and places where different actors (policy makers, civil servants, NGOs, citizens, start-uppers, entrepreneurs, etc.) receive continuous stimuli to engage in innovations that fulfil specific needs (be they market, organisational or community related).