Functioning transportation networks are a key element for cities and towns across the Globe and are a precondition for economic activity and social participation. At the same time, economic and social benefits of urban mobility are frequently accompanied by negative side effects such as congestion, social exclusion, accidents, air pollution and energy consumption.

Since the mid-20th century, the negative side-effects of urban transportation have particularly become apparent in the metropolitan areas of developed countries. Rising car traffic volumes are increasingly causing lost economic productivity, environmental degradation and affect the quality of life in cities in general. In developing countries, rapid urbanization and motorization in recent decades in combination with insufficient investment in infrastructure has led to similar problems, often exacerbated by urban poverty and social exclusion.

In the face of a rising global population, continuing urbanization and the emergence of megacities, there is heightened urgency to apply solutions in the urban transport sector that contribute to sustainable urban development approaches and comprehensive responses to the impacts and causes of global warming while enabling mobility for the population. Sustainable Transportation policies have to consider the multiple social, economic and environmental dimensions of urban transport and formulate effective policies and investment strategies to reconcile competing interests between different modes of transport and societal groups.

The main challenge for UN-Habitat is to find ways to promote urban productivity and improved living and working conditions for urban populations by appropriately meeting transport needs in an economically efficient and environmentally and socially sustainable manner.