After the 9/11 attacks, a large number of countries have undertaken programs to bring together all relevant information in the fight against terrorism in order to be able to produce integrated threat assessments. Some of these initiatives have even included the establishment of new structures often referred to as 'fusion centers.' At the end of 2006, such a fusion center was also set up in Belgium - the Coordination Unit for Threat Assessment. In this book - which contains an introduction by Gilles de Kerchove of the EU Counter-Terrorism Coordinator as well as a concluding chapter by professor Peter Gill - the Belgian Standing Committee I collects contributions from European countries that have created a similar body or that have attributed the 'all-source threat assessment' assignment to an existing body. Besides the EU Joint Situation Center, no fewer than 19 EU Member States have participated. The result paints a specific and valuable picture and gives a unique insight into the way integrated analyses are produced, because all contributions are written by people from within the fusion centers. The chapters cover topics regarding the countries' intelligence and security landscape in the fight against terrorism: the drawing-up and dissemination of threat assessments, the legal framework, the organization, resources, management and authority of the body or structure, and internal and external review of the activities. The resulting overall picture is perhaps best described as a kaleidoscopic vision. Some Member States have set up a new body while others use existing services. Sometimes, the methodology is highly formalized whereas others use informal arrangements and work through consultation forums. For some services, threat assessment is their core business; for others, it is just one aspect of their operations. Some services only carry out ad hoc analyses, some only strategic analyses, and some do both. In some countries, the integrated threat assessment assignment has been entrusted to several services at the same time, while other countries have clearly assigned the task to a single service. The book provides a comprehensive picture on which all countries can draw, in order to create more accurate, reliable, and timely threat assessments for policymakers or for operational services.