The Norman Paterson School of International Affairs (NPSIA ( nip-SEE-ə)) is a professional school of international affairs at Carleton University that was founded in 1965. The school is housed in Richcraft Hall, on Carleton's campus in Ottawa, Ontario, Canada. Students, alumni and faculty of NPSIA are referred to as NPSIAns ( NIP-see-ən).

NPSIA is Canada's oldest school of international affairs, founded during what is commonly considered a golden age of Canadian diplomacy. The school offers an interdisciplinary approach to the study of global issues, divided into eight fields.

In 2007, a poll of Canadian academics, intended to determine the best professional masters programs in international affairs, ranked NPSIA at No. 2, tied with Georgetown University, and ahead of programs at universities like Harvard and Columbia. A 2019 survey of Canadian academics in international affairs confirmed NPSIA as the most recommended school in Canada for students seeking a career in policy.

NPSIA is a founding member of the Association of Professional Schools of International Affairs (APSIA), a group of public policy, public administration and international affairs schools.