Foreign assistance is a fundamental component of the international affairs budget and is viewed by many as an essential instrument of U.S. foreign policy. Since the terrorist attacks of September 11th, 2011, foreign aid has increasingly been associated with national security policy. U.S. foreign aid policy has developed around three primary rationales: national security, commercial interests and humanitarian concerns. These broad rationales are the basis for the myriad objectives of U.S. assistance, including promoting economic growth, reducing poverty, improving governance, expanding access to health care and education, promoting stability in conflictive regions, promoting human rights, strengthening allies, and curbing illicit drug production and trafficking. This book provides an overview of the U.S. foreign assistance programs, foreign aid spending, delivery of foreign assistance, and public-private partnerships (PPPs).