That resources are diminishing is a commonplace, but scarcity is about much more than the destruction of our natural resource base: it is a socially and economically constructed condition that affects us all, and will increasingly do so. Scarcity Exchanges is a series of exchanges on and around the topic of scarcity, bringing together some of the leading thinkers in the field to expound on one of the most pressing, but often avoided, issues of the day.

Alfredo Brillenbourg's talk is entitled ‘Simply Built - a chance for our urban planet’. Today of the 6.89 billion world population 3.44 billion (50%) live in cities. Slums concentrate 1 billion (29%) of humanity in poorly built and badly serviced neighbourhoods, typically in the moderate climate of tropical South-America, Africa and Asia. In Brazil the degree of urbanization is 87 % with São Paulo being the largest city in South America with approx. 20 million inhabitants in the metropolitan area. The favelas of São Paulo for example house approx. 1.34 million people, and are characterized by limited or no basic centralized infrastructure, a lack of utilities, public space and services.

The challenges of how cities can provide public services year around, especially in moments of crisis or scarcity, are fundamental for their continuous development and success. Without clear existing land property regulations the Favelas can be seen as an open laboratory for research. As such, they offer a unique opportunity for experimentation that allows for the introduction of leapfrogging alternative concepts of spatial organization, environmental qualities, and strategies for sustainable decentralized infrastructure.

One of the most urgent demands in favela upgrading is the synergy between technology, the existing built space, and environmental aspects. This indicates a research direction that aims to achieve a healthy and quality environment for its users and a more efficient use of natural resources in urban settlements, especially in relation to energy, water, waste, vegetation, landscape design, and local climatic conditions.

David Satterthwaite is a Senior Fellow at the International Institute for Environment and Development (IEED) and editor of Environment and Urbanization. He has been contributing to the work of the Intergovernmental Panel on Climate Change on urban adaptation since 1998 and has written or edited various books on urban issues. Alfredo Brillembourg is founder of the highly influential Urban-Think Tank (U-TT), co-editor of the widely-cited book Informal City: Caracas Case, Professor of Architecture and Urban Design at ETH Zurich, and, together with Hubert Klumpner, recipient of the 2010 Ralph Erskine Award for innovation in architecture and urban design.