The US is by far the world’s largest humanitarian donor. In 2000, US relief aid totalled nearly $1.2 billion, around a third of all humanitarian assistance. Despite this predominance, humanitarian aid occupies an increasingly uncertain place in the country’s foreign policy. The percentage of gross national product allotted by the US government to foreign assistance has stood at or below 0.1% – lower than at any time in the past half century. This paper examines trends in US humanitarian policy, and assesses how these trends are reflected in the changing architecture of US assistance.