The Sao Paulo metropolitan area has faced increasing transportation problems in recent decades, most of which are related to the sharp growth in the use of private transportation and the corresponding decrease in the use of public transportation. This paper analyzes current transportation and traffic conditions in the Sao Paulo metropolitan area and the factors that shaped them over the 1967-1997 periods. Quantitative data from four subsequent origin-destination surveys were used. During this time period, transport progressively changed towards a motorized system, first with the intense use of buses and finally with the large increase in the use of automobiles. Public transport services experienced severe supply and quality problems and increasing fares led to the exclusion of a large number of users. Negative externalities related to the increasing use of the automobile--such as traffic accidents, congestion and pollution--skyrocketed, threatening the sustainability of the metropolis. All such consequences were propelled by the lack of coordination among urban, transport and traffic policies, the abandoning of public transport, and the political, ideological and economic support given by transport and traffic authorities for automobile use. Although it is clear that the current transport model is not sustainable, no real political agreement has emerged to change it, suggesting that even harsher negative consequences will have to be faced until a new vision and proposals are developed
