This paper deals with fire safety according to the following perspectives: 1. fire safety on the construction site; 2. fire safety in buildings during their construction; 3. fire safety in buildings after their completion. The paper comprises three separate parts. In the first part, an analysis is made of the main differences among the three perspectives referred to above, from the point of view of fire safety. In the second part, an approach is made to the legislation related to each of those perspectives and to its difficulty in covering effectively such different situations as those presented. Lastly, in the third part, a perspective is presented about the evolution of new ways of supporting the fire safety project, by developing and implementing computer-based mathematical models for carryng out an overall assessment of the fire hazard in buildings. In this part, a brief desciption is also made of the first stage of a model for analysis of the fire hazard in buildings, which is under study at Laboratorio Nacional de Engenharia Civil - National Laboratory of Civil Engineering. The potentialities of this model are described, both in terms of description of the building and in terms of development of the method of evacuation.