Discussion of the factors that cause the deterioration of buildings. These factors can benatural (climatic conditions, catastrophies) or man-made (atmospheric pollution being the principal cause). The effects of atmospheric pollution on construction materials are brought about by a mechanical action (the blackening and staining of facades, abrasion of finishes) and by a chemical action (primarily due to sulphur dioxide). The climatic conditions such as relative humidity and temperature favor certain deterioration reactions. Solutions are proposed to fight the damage; to protect and restore buildings in polluted towns, i.e., reduction of pollution emission, to choose carefully sites for new pollution sources; to utilize extensive tree plantings in protective perimeters around the buildings; and to use protective coatings. Cl. C -- AATA