At the beginning of the 21st century, for the first time in human history, the population living in urban areas has surpassed that living in rural areas. Currently 1.6 billion people in Asia-Pacific, or 40% of Asians, live in urban areas, but by 2030, a majority (around 2.7 billion) will live in cities and towns. This means adding a new town of 137,000 people every day for the next 22 years. Latin America is currently the region with the highest percentage of urbanization 75%, this trend is expected to continue adding population to megacities in the region with already saturated infrastructure. These trends, coupled with population growth, represent a considerable challenge in delivering cost-effective and affordable services to the population.

They represent also an important challenge in terms of environmental sustainability, as cities are responsible for approximately 75% of all energy use and 80% of all greenhouse gas emissions. Cities and towns are, therefore, increasingly important geographical and governance levels to address sustainable development challenges.

Infrastructure systems are integral components of urban development and a deciding factor in delivering services to communities, and in supporting economic growth, but also in determining environmental impacts. Infrastructure is not only costly and very intensive in resource use, including energy, water, materials and land, but it also locks cities into consumption patterns for decades. Buildings, for example, are estimated to contribute up to 40% of energy use and greenhouse gas emissions over their life span. The choice of infrastructure is thus critical in determining the efficiency and effectiveness of service delivery, as well as the environmental impacts of urban areas, including energy use and greenhouse gas emissions.

Traffic congestion costs and poor-quality infrastructure have been found to be the main factors negatively influencing competitiveness of urban areas. Lack of integrated planning and investment in public transportation can result in high social and economic costs. Lack of attention to environmental and social aspects in infrastructure development reduces the profitability of investments in infrastructure as well as opportunities for contributing to economic growth and improving quality of life. In turn, environmental quality and a more sustainable spatial approach enhance the livability of a city, and thus its attractiveness to foreign direct investment.

Cities in Asia and Latin America are at a crossroads in developing and expanding infrastructure. Choices made in urban infrastructure development will have a major bearing on the competitiveness, quality of life and sustainability of cities in the region. The need to take social and environmental implications into account is clear.