State structures are the dominant but not the only source of policy innovation as there is a need to consult other interests for information. Think tanks seek to provide this kind of information and occasionally play a dynamic role in identifying problems. The policy-makers rely heavily on think tanks for a great deal of analytical inputs and advice. Think tank culture in South Asia is a new phenomenon as compared to US and other European countries. Think tanks in India -- like Institute for Defence Studies and Analyses, New Delhi; Indian Council of World Affairs, New Delhi; Institute for Peace and Conflict, New Delhi; and Centre for Policy Research, New Delhi -- provide world level research facilities on foreign policy and other strategic issues. In Pakistan, think tanks concentrating on foreign and security issues include Institute of Policy Studies; Institute of Regional Studies; Institute of Strategic Studies; Jinah Institute; and Islamabad Policy Research Institute. Prominent think tanks in Afghanistan are Institute for Afghan Studies; Afghanistan Watch; and Kabul Centre for Strategic Studies. This book explains and examines the role of think tanks in public policy formulation in US and South Asian countries, viz. India, Pakistan, Afghanistan, Bangladesh, Nepal, and Sri Lanka.