All over Europe, but in the United States and China too, the public and private buildings inherited from the 1960s and ’70s are today liable to a libido delendi headed for its own perversion. The destructive option towards a built past deemed useless, ideologically incompatible with the present or just plain “ugly”, is currently seen as a keyword shared by many public authorities. These are convinced that demolition, in view of the construction of newer and more modern units, can in itself guarantee formulas for living that are more efficient and better suited to future metropolitan life. But if yet another version of Leopardi’s magnifiche sorti e progressive ought to find us at least a little more sceptical towards this kind of refrain, the muscular (and financial) fascination of the new, based on erasing the existent biologically unfit to survive, still casts a heavy smokescreen over all critical thinking about the destiny of de-functionalised buildings. The reflections by Domus in the Intersections feature on Urban Retrofitting do not just compare the purely pragmatic consequences of the demolition option with other possibilities, but attempt to raise more complex issues. The aim is to examine the fate of our recent architectural past in a different, and theoretical, light. Have we really asked ourselves how a built heritage, which has fallen into disuse but is nevertheless a settled feature of a city’s cultural landscape, should be considered in the light of perception and memory? And how the (mostly historical and aesthetic) criteria of evaluation are justified epistemically, to decide whether or not to conserve a piece of no-longer-functional architecture such as a derelict Soviet building complex or a ruined Norman observation tower? To put it more plainly, we wondered: why do we take it for granted that a Norman ruin should be conserved or restored, yet equally for granted that the Palast der Republik be pulled down? We have looked at the fate of no-longer-functional architecture from an angle alternative to that of the logical demolition/reconstruction pair.Underlying the idea of regaining and reinserting, within a housing cycle, a built heritage that has fallen into disuse, by following a secular and unbiased rule of renovation, is a deep awareness of the need to act more conceptually than architecturally. This would avoid buildings being labelled obiecta delenda.This perspective can if you like be read by paraphrasing Jacques Derrida in view of Lacaton and Vassal (but the order can be reversed): just as every construction embodies the germs of its deconstruction, so also does “largescale social housing carry the germs of its own improvement”. To give more through less, to build housing by means of failed housing: Lacaton+Vassal, Raumlabor, Cyprien Gaillard and Monika Sosnowska, each in their own way, adopt this approach to reload with a sense of the architectural (and social, moral and aesthetic) a whole lot of buildings that are gradually wasting the meaning of their presence.