Rehabilitate, in the strict sense of the word, means to enable again, to enable once more, just that this time we don’t turn back to the past but to the future. This time the end is to guaranty the life of the building in question and frequently implies its complete modernization and sometimes, even shifting its use. When we deal with modernist buildings, as Casa Oller de Salvat i Espasa, the Palau Macaya de Puig i Cadafalch or the building where we have our office, Casa Mayol, build for the 1888 exhibition, nobody doubts the importance of the patrimony on which we are intervening. However, patrimony is everything that has been built, and that is why several interventions are preented, some carried on a Georgian building in London, in several 19th century buildings, some in the Ensanche de Barcelona but also, on “modern” buildings from 50-60s of the past decade, from renowned architects like the Inmobiliaria General headquarters in a building by Busquets, that of the Mutua Madrileña from the Castellana in Madrid by Gutierrez Soto or Winterthur’s Auditorium and Training Centre at the L’Illa Diagonal complex by Rafael Moneo and Solà-Morales.