We have considered it appropriate to publish in este second issue of the collection the study of the grouping of high-rise collective housing based on the configuration of four dwellings per floor, which in some way can be understood as a variant of the usual contemporary block of two dwellings per landing. This circumstance has been considered of m interest for the typological study due to the frequent incorporation of central courtyards to ventilate las interior areas of las dwellings and as can be seen there is a gr