Fernando Serpone Bueno and Veridiana Sedeh
In fast-urbanizing planet, Sao Paulo develops model toolkit to improve housing for poor, dispossessed.
Sao Paulo
São Paulo's Favela Paraisopolis. Photo: Roberto Rocco

São Paulo Seventh largest among the world's metropolises and the linchpin of Brazil's booming economy, São Paulo presents a globally relevant case study of stepped-up efforts -- but continued deep challenges -- if cities are to correct the deep poverty and environmental perils of massive slum settlements.

Jay Walljasper
Chicago models ambitious Climate Action Plan to slash carbon emissions and handle warming

Chicago Nation states' failure to reach far-reaching accord at the Copenhagen summit may have dashed-- for now -- hopes of unified global action on climate change. So who must now step forward to face the 21st century's gravest problem? Clearly, it's cities and metropolitan regions, home now to a majority of mankind, generators of 80 percent of the world's carbon emissions.

Birgit Heitfeld
Berlin's "Neighborhood Mothers" program reaches out to immigrants, suggests global model

Berlin Turkish bakeries, delis, Oriental supermarkets and Döner Kebab (burger) stores. Mosques, hairdressers, a Turkish Airlines travel agency and Arabian shops. The mix gives the Berlin neighborhood, or "kiez," of Northern Neukölln a colorful, quirky feel. Some call it "Little Istanbul," others Berlin's "Lower East Side" for its companion mix of artists and intellectuals.