The Washington International School (abbreviated as WIS; Spanish: Colegio Internacional de Washington; French: École Internationale de Washington) is a private international school in Washington, DC. Established in 1966, WIS was the first school in the Washington area to offer the International Baccalaureate (IB) program. The school has two campuses: the primary school (grades PK–5) in Georgetown, and the middle and upper school (grades 6–12) in Cleveland Park. The middle and upper school campus is located on the grounds of Marjorie Merriweather Post's Tregaron Estate.