As part of an effort to think about Europe's long-term security needs, the European Defense Agency requested this study of what sort of world the European Union will inhabit in 2025. The answer: a dangerous and highly uncertain one, in which Europe will not necessarily thrive. Some of the highlights of that future include a world population that grows by 23 percent, compared with 2 percent for the EU, leaving Europe at 6 percent of the world's total population in 2025; a continued shift of economic power to China and India; a rise in overall energy demand by almost 50 percent, with fossil fuels remaining the world's primary energy source; and potential instability or authoritarianism on Europe's borders. Internally, the EU faces a rapidly aging population that will put a strain on public budgets and health-care systems, the outsourcing of some key industries, and severe energy dependence on Russia and the Middle East. None of this will be big news to anyone, but this volume should be seen as a warning to Europe's leaders that now is the time to start preparing for some real challenges ahead.