Science has a way of transcending borders.  It has done so from the beginning, going back to the ancient Greeks, but as the world grows more interconnected in so many ways, the pace of international collaboration in science has in recent years picked up markedly.  To take just one indication of this trajectory, in 1996 25 percent of scientific articles were written by authors from two or more countries. Today it’s 35 percent and climbing.  As New York University president John Sexton points out in the essay that kicks off this special report, science today is more collaborative than it’s ever been. To cover this important trend, Scientific American and Nature teamed up to assess The State of the World’s Science.

Our Global Science Scorecard ranks nations as to how productive they are in science—not only on the quality and quantity of basic research but also on their ability to project that research into the real world, where it can affect people’s lives.

We also examine the movement of scientists and ideas, and how "brain circulation" is changing the way science is done, how it is funded and the kinds of questions it addresses.

By sifting through data, talking to experts and conducting a survey of 2,300 readers around the world, we have identified underlying trends in scientists’ movements, investigate what is driving them and explore how they may change. At stake is the shape of global science and the prospects for individual countries that hope to build up — or preserve — their research strength. The fruit of this work is Richard Van Noorden’s article on migrating scientists.   An accompanying graphic shows where these scientists have gone—a picture of the global diaspora.

Our special report also explains some of the more salient trends behind the globalization of science and what it means. Why, for instance, does Germany still make things? While the U.S. and other developed nations lose manufacturing to countries with lower labor costs, Germany has managed to keep a high-tech edge through a close partnership between government, academia and industry. We take a close look at China's rise to world-class status, which shows that the Middle Kingdom still has to figure out how to raise the bar not just at the very best labs but throughout all its universities.

We also look at the factors behind the success of the U.S. and the challenges of staying on top. One of the reasons scientists in the U.S. do top-flight work, argues Paula Stephan of Georgia State University, is that the best are better paid–in other words, income disparity in science is not all bad. And Michael Crow, president of Arizona State University, gives us his bold plan for raising scientific literacy: reinvent the way science is taught.

If anyone knows about the changing international scene, it’s Paul Nurse, former Rockefellar University president and now head of the British Royal Society. “Science," he says in a Q&A, "is a catalyst that can break down the gulf between nations.”

We are pleased to present this joint project between Nature and Scientific American.