[pt] A dispersão da mancha urbana das cidades provoca alto custo para toda a população, com a necessidade de investimentos em saneamento, transportes e equipamentos urbanos, além do problema da poluição e desmatamento causados por essa expansão. Em casos como o da cidade do Rio de janeiro, a mancha urbana ocupa praticamente todo o território municipal e se desenvolve em áreas ainda desprovidas de infraestrutura que suporte novos empreendimentos, enquanto outras, melhor estruturadas, ficam estigmatizadas por conceitos urbanos pejorativos e desprestigiadas pela sociedade - os seus chamados subúrbios, hoje conhecidos como Área de Planejamento 3. Formam-se, com isso, vazios urbanos em áreas próximas ao centro, que poderiam ser melhor aproveitados para termos um território mais compacto e poupador de recursos públicos. O atual Plano Diretor da cidade estabeleceu como zonas de incentivo áreas antes desprestigiadas, em quase toda a Zona Norte e parte da Zona Oeste, sendo um ponto de partida para reversão do atual quadro de crescimento desordenado e segregatório da cidade. / [en] Rio de Janeiro has had a fragmented model of expansion, where many new regions occupied not have transportation and sanitation infrastructure, and old areas, structured, tend to be disparaged and stigmatized as places of low social value. The effects on the city is catastrophic, affecting the routine of all the population and hindering the control of the territory by the government. While there were new areas to grow, the city took advantage of that. Many neighborhoods were born, evolved and died, while new spaces were created and encouraged. Came to Barra da Tijuca, the greatest example of how Rio de Janeiro has expanded to meet the desires of a particular group in search of a safe and elitist environment. Condos upper middle class were built and attracted people from all over the city and, in parallel, its sewage was dumped in the lagoons of the neighborhood. While a new Rio grew, much of the city was deteriorating, especially downtown and North Zone. In the central region, the idea of transferring downtown to Barra da Tijuca gained strength, with large companies moving into this new neighborhood. Modern buildings, wide open spaces and parking were the main differences between the two regions. In the residential aspect, concern for downtown was virtually nil. In the North Zone, with the increase of slums and violence, traditional neighborhoods were no longer the focus of the middle class carioca, with stagnating real estate investments over time and making the region passed by a process of forgetting his relevance within the context of the city, having his image associated with violence and crime. In areas called suburbian, the situation was even worse. The old industries have moved to other cities due to the daily violence of those neighborhoods, highlighting Benfica, Bonsucesso, Ramos and Penha, suffering a massive stagnation over the past decades. Associated with urban problems, prejudice was responsable for the not occupation of a large space in the city, well structured and located. But none of this was seen as a problem, but as a solution, because in Rio there were still many areas to grow and receive new residents, not being interesting recover and encourage the occupation of what had actually structure to receive new ventures. The thought of rejection of old areas and interest in new lasted nearly three decades and, as a consequence of this neglect, we have seen emerge an ancient and undervalued city and another one new and prosperous, resulting in a decentralized Rio and full of empty urban, increasingly dependent of transport, sanitation and opening new routes, generating costs for the entire population. Analyzing the urban area in Rio, in North Zone, we can see how there is a waste of urbanized areas, where there is a structured urban space, with transportation and sanitation system established, but underutilized and virtually without good projects being introduced. In certain parts of West Zone, investments are numerous, without a previous and efficient infrastructure that can receive all these investments. This is a contradiction. Currently known as Planning Area 3 (AP 3), a huge and discredited region in North Zone is in a strategic location, but is stigmatized by the media and society with pejorative concepts of class, who treats it like a suburb, but the application of that name ends up being contradictory, because, in Rio de Janeiro, this concept is associated with an etymology and not with a urban fact. There are in AP 3 urbanized neighborhoods and near downtown, but they are viewed negatively, often caused by so-called opinion leaders. AP 3 is the gateway of the city, with a strategic location to anywhere else in the city, state, country and abroad (the international airport is located there). It is the most populated area in the city and needs to be well treated, as a new investment option, regardless of titles assigned to it. With its proper use, we would have a less process of expansion toward the West Zone, giving to the Rio a efficient urban development, integrator and spending few public resources, resulting in a territory less dispersed and more egalitarian. The lack of investment in AP 3 has brought, besides the widespread abandonment, tragic consequences not only for the 38 per cent of the population carioca living there, but also for the entire city, which bears the overall expenditure of the municipality. Carioca population grew between 2000 and 2010 from 5,857,904 to 6,320,446 inhabitants, and the population density grew from 4880.37 to 5265.81 hab/square km. Analyzing the five planning areas, we observed a population growth across all APs in the nineties, but the representative of each one in the citys total population was redistributed. The AP 3, which concentrates most of the population of Rio, had a dicrease from 40.20 per cent to 37.96 per cent hab/square km, while the West Zone had a considerable increase in that number. The West Zone (Barra da Tijuca, Recreio dos Bandeirantes, Jacarepaguá e Vargens) is the area that received the most investments and incentives to be occupied, with only 14.39 per cent of the population residing there. There is still no efficient system of sewerage, transport, sidewalks and street paving. Nevertheless, we can see that area envolving more and more, causing a collapse not only within the limits of the West Zone, but also affecting the traffic throughout the city. In contrast, AP 3, with nearly 38 per cent of the municipal population, has been losing its representativity, due to the lack of policies to encourage the attraction of new residents and provide better services to the current. A city like Rio de Janeiro, where there is still no efficient mass transport, should be more compact and its residents served by quality services in short rays, eliminating the dependence on shifts that require the use of own vehicles. The consequences of urban sprawl is what we see nowadays, like the constant traffic jams, due to the dependence of vehicles from those who live in areas furthest from downtown, the high cost of deployment transportation system to meet these new areas, need for sanitation base infrastructure, paving and lighting. The big question is, if there is a region still largely in its horizontal and already endowed with infrastructure, as the AP 3, investments in development and attracting new residents would be a way to save public money and take advantage from the current urban area of the city, contributing to a truly sustainable development. Rio de Janeiro does not have more growth cluttered spaces and building in prime areas are increasingly rare. Seeing the AP 3 as a growth vector of Rio is an economical way to have an efficient and inclusive urban development. This need has been ratified by legislation through the Complementary Law 111/11, which determined the incentive of that area and some adjacent. AP 3, because of its size and diversity, demands varied solutions, but the common denominator is the need to stimulate the formal residential occupation, urbanization, retrenchment in slums, the recovery of peripheral areas to them, that has been assuming characteristics of informality, and improving the infrastructure and quality of the transport system. There are many obsolete and underutilized areas that will enable a transformation in the way of inhabiting the city. If there is a global awareness of the urban territory, either in Rio de Janeiro or any other city in the world, the concept of sustainable growth is meaningless, with neighborhoods rising, developing and dying, wasting past spending and future spending provoking. Cities can not continue with thoughts segregatórios class and should be properly used and maintained, valuing its past and controlling the growth process on expensive areas untouched, becoming an integrated environment and easy to be used and administered. Despite this negative picture, a more attentive enough to discover the enormous economic potential of the AP 3. The housing market in certain spots is heated and there are high expectations of its expansion with new public and private investments that are occurring. Life in neighborhoods still retains an aspect of good neighborliness, preserving a quality of life now lost in the more developed districts of the city. We can already notice a special attention to the region, with new public and private investment, with little prospect of improvement in visibility and consolidation of growth vector proposed by the current master plan.