The affordable housing issue will probably never be resolved because it is intrinsic to the economy and social development of cities. What is more, as has been seen, there is a clear delay in certain European states that have not known how to keep a significant part of housing out of the speculative market. Without significant provisions for affordable housing, countering individual preference for ownership will become difficult, and efforts will have to be tripled for European cities to have housing markets like those of Amsterdam or Vienna. These states can no longer count on the asset of unlimited land and will therefore have to invent compact formulas to optimize the buildable areas. It is a convenient form of housing, with a medium- to long term business model that can bring a great deal to the city. On the one hand, it contributes to producing affordable housing units. On the other, the hybrid nature of the buildings, the co-management of the shared spaces, and the activity of the residents over the 24 hours has the potential to build blocks that are more than just a number of apartments in the neighbourhoods in which they are placed. The 2007 financial crisis widened social inequalities and the recession significantly increased the perception that European households allocate too much of their money to housing. Today, in most European countries, more than a third of citizens recognize that they feel greatly limited by the cost of housing. On the one hand, this can be explained by a process of decelerated urbanization in Europe. The trend in urban areas is no longer the growth of thirty years ago, and therefore not as much new land is generated. There is growing concern about environmental sustainability and the reduction of the ecological footprint has become fundamental for all municipalities; though in recent decades the phenomenon of suburbanization had expanded across the metropolitan areas of the whole of Europe, with isolated, low-density residences, increasingly there is awareness of the need to keep growth compact and preserve the rural land. Dispersed urban areas have an indirect environmental cost and a disproportionate economic cost on municipalities, which have to provide urban services and public transport to isolated areas that are sparsely populated. Taking land to increase the housing stock is in conflict with the territorial aspiration to preserve natural areas.