An in-depth, multimedia look at climate change, its global impact, and efforts to combat it.

Migration is seen as the product of desperate circumstances, but increasingly it is the byproduct of success—improved child survival followed by a booming young-adult population.

Health and infectious diseases have shaped the history of urbanization, but it is cities that will define the future of global health.

Japan's constitutional debate is about not simply the document's past but also the nation's ability to respond to twenty-first-century challenges.