As recent events demonstrate, the manifestations of Islamist extremism in Europe are manifold. They range from youngsters who reject both government and academic attempts at multiculturalism to radical imams who influence their congregations against their host countries to fundamentalist converts who believe the West is on a crusade to destroy Islam. Chat rooms on the Internet are used with powerful effect to proselytize, recruit, radicalize, fund raise, train, and plot acts of terrorism. In part to counter violent Islamist extremism, the U.S. National Intelligence Strategy seeks to: (1) develop innovative ways to penetrate and analyze the most difficult targets ; and (2) strengthen analytic expertise, methods, and practices; tap expertise wherever it resides; and explore alternative analytic views. Consequently, the director of national intelligence has given top priority to enhancing outreach to the myriad sources of expertise and open source information that can play a decisive role in countering threats such as terrorism. Over the past year, the CSIS Transnational Threats Project operated and tested a global Trusted Information Network (TIN) devoted to critical threat issues demonstrating that structured interaction with nongovernmental experts on the periphery can provide innovative, alternative analysis and perspectives. Islamist extremism in Europe was explored by the TIN s internationally recognized experts, even as daily events in Europe illustrated that al Qaeda inspired terrorists continue to proliferate among Muslim communities there. TIN members, in a collaborative online setting, contributed fresh information and perceptions about the extremists route to violence and their aspirations. This report reviews the workings of the CSIS network and demonstrates the contribution such a TIN can make as a force multiplier for intelligence in the information age.