This is the first in a series of reports by the Majority and Minority staff of the Senate Committee on Homeland Security and Governmental Affairs (Committee) on the threat of homegrown terrorism inspired by violent Islamist extremism. The Committee initiated an investigation into this threat during the 109th Congress under the leadership of Chairman Susan Collins (R-ME). The first hearing on the homegrown threat considered the potential for radicalization in U.S. prisons, including an examination of the activities of Kevin Lamar James, an American citizen. While in prison, James adopted a variant of violent Islamist ideology, founded an organization known as the Assembly for Authentic Islam (or JIS, the Arabic initials for the group), and began converting fellow prisoners to his cause. Upon release, James recruited members of JIS to commit at least 11 armed robberies, the proceeds from which were to be used to finance attacks against military installations and other targets in southern California. James and another member of the group eventually pled guilty to conspiring to wage war against the United States. The James case is only one example of how the violent Islamist terrorist threat has evolved and expanded since the terrorist attacks of September 11, 2001. Al-Qaeda planned the 9/11 attacks and recruited the hijackers abroad before sending them to the United States to make final preparations for the operation. The 9/11 hijackers were indoctrinated into the violent Islamist mindset long before they set foot in the United States. As the James case and others illustrate, however, radicalization is no longer confined to training camps in Afghanistan or other locations far from our shores; it is also occurring right here in the United States. During the 110th Congress, under the leadership of Chairman Joseph Lieberman (ID-CT), the Committee continued its investigation into the threat of domestic radicalization and homegrown terrorism inspired by violent Islamist ideology. The Committee has held five more hearings exploring a range of subjects, including an assessment of the homegrown threat in the United States, the European experience with domestic radicalization, the federal government's efforts to counter the homegrown terrorist threat, the role of local law enforcement in responding to the threat, and the Internet's role in the radicalization process. This staff report concerns the last of these subjects - how violent Islamist terrorist groups like al-Qaeda are using the Internet to enlist followers into the global violent Islamist terrorist movement and to increase support for the movement, ranging from ideological support, to fundraising, and ultimately to planning and executing terrorist attacks. In the second section of this report, we examine the increasing number of homegrown incidents and the judgments of the intelligence and law enforcement communities that there will likely be additional homegrown threats in the future. The third section explores the four-step radicalization process through which an individual can be enticed to adopt a violent Islamist extremist mindset and act on the ideology's call to violence. Section four identifies the disturbingly broad array of materials available on the Internet that promote the violent Islamist extremist ideology. The availability of these resources is not haphazard, but is part of a comprehensive, tightly controlled messaging campaign by al-Qaeda and like-minded extremists designed to spread their violent message. The fifth section of the report examines how these materials facilitate and encourage the radicalization process.