Barcelona is a consolidated city. Seen from the air, it could seem like a completed city, with no room for new transformations. However, as pointed out by Bernardo Secchi, an Italian urban planner and thinker of the contemporary city, "the territories and cities we see are the result of a long process of cumulative selection that is still underway." Barcelona is not a finished project, but rather finds itself in another stage of a history that remains open. The city we have inherited is the fruit of decisions accumulated over decades, but also of the decisions we make today and which will determine its future.Urban planning is precisely this exercise in selection. Choosing what we preserve, what we transform, what we intensify, and what we recover. And today, this selection is conditioned by two major challenges that will redefine urban living conditions: climate change and the affordable housing crisis.These challenges question many of the certainties upon which the imaginary of the progress of the modern city was built, but they also offer the opportunity to build a new urban agenda. An agenda that is not based on nostalgia or fear of uncertainty, but on the capacity for adaptation. As Zygmunt Bauman noted, "to navigate uncertainty" cities should prioritize the adaptability of their urban fabrics rather than the imposition of rigid and definitive forms.Barcelona's goal is, therefore, to prepare for this future. Adapting means changing ways of doing things, revising inherited mental frameworks, and assuming that we will have to obtain better results with more limited resources. Building more housing without having large land reserves. Increasing climate comfort in recurring drought scenarios. Improving urban quality by intervening in an already built city.