Understanding and improving the Brazilian informal settlements known as favelas will require more information about the slums -- especially in the field of mapping.
"Brazil is known for having naked extremes of wealth and poverty. This has not changed significantly in centuries of political upheavals that have included slavery, colonialism, empire, nationhood, modernization, dictatorship, and democracy. One of the most enduring images of how this affects Brazil's cities is the favela. Favelas are Brazil's urban informal settlements, which have become familiar, even iconic images of informal urbanity itself. However, even with their notoriety, representations of favelas are often incomplete or misleading. While the "culture" of the favela, usually reduced to samba music and dance, has historically been represented in the broader Brazilian culture, detailed information about favelas-how many there are, where they lie, how big they are, what their population is-was missing or suppressed."
"Representations of favelas on maps of the city vary. Sometimes these dense urban neighborhoods are simply not included, and in their place are green areas that look like parks. If they are included on maps, they are usually coded in an uncertain or less committed strategy of representation. With the advent of aerial photography and the involvement of the government in favela upgrading programs, maps began to be produced for both planners and police. Archives and statistics on favelas have been assembled, but are filed separately, in a grey zone between official urban data and the realm of what can't be represented or understood. Maps are produced based on government aerial photographs, not information gathered on the ground. As such, they are no more than traces of photographs. If one manages, as I did, to obtain access to the maps in the city planning department, one finds that these documents are filed separately from the city's official plans, which do not show the buildings and streets of the city's favelas. Rio has a progressive plan for upgrading favelas, but its geographic representations have not caught up."