Forget the G-7 and the G-20; we are entering a leaderless "G- Zero" era- with profound implications for every country and corporation. The world power structure is facing a vacuum at the top. With the unifying urgency of the financial crisis behind us, the diverse political and economic values of the G-20 are curtailing the world's most powerful governments' ability to mediate growing global challenges. There is no viable alternative group to take its place. The United States lacks the resources and the political will to continue as the primary provider of global public goods. China has no interest in accepting the burdens of international leadership. Europe is occupied with saving the eurozone, and Japan is tied down with its own problems. Emerging powers such as Brazil, India, and Russia are too focused on domestic development to welcome new responsibilities abroad. The result is a G-Zero world in which no single country or bloc has the political or economic leverage-or the desire-to drive a truly international agenda. Ian Bremmer explains how this will lead to extended and intensified conflict over vitally important issues, such as international economic coordination, financial regulatory reform, trade policy, and climate change. We are facing a time of profound uncertainty. Bremmer shows who will benefit, who will suffer, and why this increased state of conflict is both inevitable and unsustainable.