By 2030, nearly 60% of the world’s population will live in cities. Megacities with over 10 million inhabitants are appearing in developing countries and will include Cairo, Dhaka, Jakarta, Karachi, Lagos and Mumbai within 20 years. The implications for slum dwellers are devastating.

Reuters/ Rebecca Cook

A city with clout. ‘Fist’ of Boxer, Joe Louis, New York.

The alternative climate summit for mayors in Copenhagen in December 2009 aims to put cities at the top of the climate change agenda. The summit’s message to heads of state, the media and citizens is that cities and local governments have a crucial role to play given they are responsible for up to 80% of global CO2 emissions: they can and will act. Indeed, cities are already making a genuine difference devising innovative approaches to mitigating and reversing the impacts of global climate change.

In this special report, Janne Nijman, of the International Law Department, University of Amsterdam, shows how cities are stepping up to the mark. City governments and their communities are participating in global processes. No longer simply places where people live and where businesses and services are based, cities are networking and collaborating with international governments and organizations at a transnational level to deal with climate change, pollution, food insecurity, social inequality, and so on. Cities are carving out a new role for themselves as independent global actors.

How are cities coping with the huge challenges thrown up by globalization, such as climate change and poverty, so glaringly evident within city borders? They are adopting a pioneering role, writes Sofie Bouteligier, research fellow at the University of Leuven, Belgium. Although the cause of many of today’s environmental problems, cities are striving to be part of the solution. The concentration of people and their activities within cities leads to environmental degradation that requires urgent action.

Mayors and city governments recognize their responsibilities and are leading the way in tackling environmental problems. They are forming powerful networks with each other across the globe and sharing information and experience. The climate summit for mayors in Copenhagen shows that cities are beginning to make a difference at a global level. In a city-centred world, they can no longer make do working at the provincial or national levels. Good urban governance now means cities must develop transnational relations and act in the global arena.