Contenu du sommaire : Villes d'Amérique Latine plus grandes que leurs problèmes ?

From the 1940s, Bogota experienced a strong acceleration of its growth. Uncurbed and largely spontaneous urbanization is then controlled, with difficulty, by an urbanism which in reality is limited to the development of the road network. Over the last twenty years the city has turned to a metropolis. Whereas spatial expansion is now occuring beyond the urban perimeter, densities in the existing area are increasing greatly. This process is to a large extent characterized by changes in the population, notably with new forms of mobility, but also in the nature of the planning process itself and in the management of urban development. In the two latter cases, despite being progessively reformulated to achieve better control, their effectiveness remains limited. Probably the processes of metropolitan growth and their effects on spatial dynamics of different forms of mobility are still inadequately integrated. This article examines this discrepancy by a diachronic analysis of the interactions over the last fifty years between spatial and demographic dynamics and the attitude of authorities, followed by an analysis of the contemporary situation.

The pilot plan of Brasilia, originally designed for a population of 500 000 inhabitants, has become, 40 years later, the "germ-cell" of a metropolis of more than 2 million people. Lucio Costa's urban project sets up the urban pattern of an entirely new urbanity. Aknowledged by UNESCO as human patrimony in 1987 and as ecologically protected area in 1994, this twofold heritage intensifies the contradictions of diffuse processes of metropolitan development. The sugestions made by Lucio Costa's "Brasilia revisitada" in 1987 and the 1996 plan of territorial organization tried to orientate the socio-spatial dynamics.

Quito, the capital of Equador, is faced with numerous challenges in responding to the strong demographic growth which has characterized the last three decades. As a result of reforms, the municipality now has competent political actors and appropriate management tools. The spatial extension of the city and the outward spread of metropolitan growth processes have been accompanied by road improvements, the rehabilitation of the historic centre and the emergence of secondary centres. However, political and economic crises as well as recent natural catastrophes (volcanic eruptions and floods) have slowed down progress in improving living conditions for the 1 200 000 inhabitants.

The concept of 'urban governance' seems to be central in the formulation of urban policy in most 'under developed' metropolises since the end of the 1980s, especially due to the influence of the World Bank. This paper examines this notion by confronting the theory of urban regimes with the analysis of a case of urban renovation based on a shopping centre in Buenos Aires. The aim is to demonstrate the theory's limits in a local context. In the Argentine federal capital, the shopping centre represented a model example of urban development, enabling experiments to be undertaken on the changing roles in the city's productive activities resulting from the withdrawal of the state. The paper studies the interactions between different urban actors in the creation of the shopping centre, and in the transformation of its environment as well as the consequences for the city.

Montevideo, a city in rapid development, is looking to define the role it plays amongst the different capitals of South America. In order to make the transition from a past which the city is currently learning to highlight to a future characterised by modernity, a development plan has been produced. The process of creating this plan was exemplary. Following a long period of little activity, Montevideo chose as mayor an architect who was also a professor and historian. The main theme of his electoral campaign was the conservation of the city's historic centre. However, the broader development plan which encompassed this project went much further than the simple physical structuring of the urban area. None of the different elements which constitute a city were neglected. An original approach characterize Mr Arana's conception of the city and the manner in which it should be governed, involving, for example, detailed discussions with the citizens on future development propositions. Based on decentralised municipal structures, the concept of the city which is emerging in Uruguay is the product of a collective will to construct differently a new capital, to create a city for everyone.

The city of Mexico will exceed 17 million inhabitants. This results from a process of urbanization which accelerated dramatically between 1940 and 1970 but which has slowed substantially since. Initially the city attracted industries but over the last twenty years, desindustrialisation has occured and the tertiary sector has been strengthened. Today the city is characterize by its duality : the contrast between the growth of an informal economy and unplanned housing and that of financial services and prestigeous buildings. Despite the brutality of theses contrasts and a social crisis, the newly elected authority of the Federal District aims to create a 'city for everyone'.

Urbanisation trends in Venezuela have changed recently. Following a period during which the accelerating growth of Caracas reinforced the primacy of the capital, enabling it to dominate overwhelmingly the rest of the urban network, it is now the growth of four intermediate towns, together with Maracaibo and Valencia, which compensate the slowing of growth in the capital. However, this restructuring of the urban system only goes part way toward producing a balanced spatial distribution of tertiary activities ; above all it has benefited the Centre-North- Coast region through a vast outward spread of the processes of metropolitan growth.