Book excerpt: This volume chronicles and analyzes the development of think tanks and public policy research organizations, while exploring the impact think tanks have on politics, public policies, and governance in the US. Think Tanks and Policy Advice in the US investigates the distinctive nature of thirty leading think tanks in America, while capturing the political and intellectual ecology of the more than 1,500 think tanks in the US. Presidents from twenty think tanks have contributed insightful essays that examine the role, value, and impact of these organizations on a national and global level. The book examines a range of key factors (partisan politics; growth of liberal and conservative advocacy groups; restrictive funding policies of donors; growth of specialized think tanks; narrow and short-term orientation of Congress and the White House; tyranny of myopic academic disciplines; and the 24/7 cable news networks) which have impacted on the ability of think tanks to provide independent analysis and advice. This text fills a gap in the available literature and will serve as a valuable reference tool for policy makers, the media, and researchers in the fields of public policy, political science, and American politics more generally.