In 1939 Sert went into exile in New York City where he worked with the Town Planning Associates, carrying out numerous urban plans for cities in South America.


Pavilion of the Spanish Republic in París (1937). Reproduction of 1992 in Barcelona.

Fundació Joan Miró in Barcelona with sculptural roof forms designed to bring natural light into the galleries[2]
In 1952, Sert held a one-year Visiting Professorship at Yale University. The following year he became Dean of the Harvard Graduate School of Design (1953–1969). There, he initiated the world's first degree program in urban design;[3] integrated the programs of architecture, planning, landscape and urban design, and taught many of today's leading architects. During this period he served on the Advisory Board of the newly created Graham Foundation in Chicago, Illinois.

In 1955, Sert founded a studio in Cambridge, Massachusetts, which in 1958 became a partnership with Huson Jackson and Ronald Gourley. Joseph Zalewski was the Associate and continued to be in the firm Sert, Jackson and Associate founded in 1963. The studio designed many well-known projects including the Maeght Foundation (1959–64) in southern France, the Fundació Miró (museum) in Barcelona (1975) and quite a few buildings for Harvard University, including Holyoke Center (1958–65), the Harvard Science Center (1969–72), Peabody Terrace (apartments, 1962–64), and the Center for the Study of World Religions at the Harvard Divinity School. Among other notable buildings in the vicinity are a complex at Boston University including its law school, student union, and main library (1960–65), Sert's home in Cambridge, as well as the Martin Luther King elementary school (1968–71), located across from Peabody Terrace. In New York, he completed the Eastwood and Westview apartments on Roosevelt Island, NYC (1976).

In 1961 Sert brought Le Corbusier to the United States to design the Carpenter Center for the Visual Arts at Harvard, and a gallery in the Carpenter Center is now named in Sert's honor. In 1981 he received the AIA Gold Medal.