"The present paper will be centered on the metamorphose of Barcelona down town. We analyse the migratory tendencies of the population from the old neighborhood , from two contradictory forces: the gentrification (Galter and Eacock 1986) and the degradation Several sociophysical circumstances conditioned the progressive deterioration of the port neighbourhood. The prosperous area created by the culture of Rome, founder of the city of Barcelona, become an important pocket of poverty, marginality, insalubrity and ruin, at the same time as a strong social movility of immigrationemigration. The municipal goverment plans to revitalize it and to make it socially and healthy healthful. The factors of gentrification will be analized in relation to the satisfaction with the environmental quality, in the objective factors from that and the intercative factors from an individual. Psychological and sociocultural factors that define a grup of simbolic perceptive and cognitive characteristics are connected with identification and appropriation from a person with his own environment and the attachment with the basic components of action and transformation. That is to say density, proxemics, territoriality and crowding. Also to simbolic, cognitive, affective and interactive factors through which a "space" becomes a "place" (P01 1989). All these factors will be inferred through the integration of a big number of fickles, that we have categorized in three groups: the personal characteristics, the economic solvency and the cultural capacity, and the satisfaction level with neighbourhood. Hereby the factors told in the anterior paragraph are related for knowing and explain wich are the migratory intention of the studied population and which factors have a bigger weight in its decision or wish to stay or emigrate from neighbourhood. The population shows a high resistance to leave its neighbourhood. Sociocultural and economic flickles, the satisfaction with the neighbourhood or the apartments, and personal rules integrate for giving answer to the intention to stay or to change. Finally its shows how the knowledge, the implication, the appropriation of the neighbourhood are the cause and the effect, equally, of the consolidation of the society and the satisfaction with the habjtat, what redounds in the purpose of permanency."