Born in Pittsburgh, Pennsylvania, and raised there and in Vienna, Joseph Leo Koerner studied at Yale University (B.A. 1980), Cambridge University (M.A. 1982), University of Heidelberg (1982-3), and University of California at Berkeley (M.A. 1985, Ph.D. 1988). After three years at the Society of Fellows, Harvard University (1986-9), he joined the Harvard faculty, where he was Professor of History of Art and Architecture until 1999. 1999-2000 he was Professor of Modern Art History at the University of Frankfurt; in 2000 he moved to London, where he was Professor first at University College London (until 2004), then at the Courtauld Institute of Art (until 2007).
Koerner organized teaching exhibitions at Harvard on Early Netherlandish Painting (1990), German Renaissance Art (1993), Pieter Bruegel (1995) and Netherlandish prints 1550-1675 (1999). At the Austrian National Gallery in 1997, he curated a retrospective of the work of his father, the painter Henry Koerner. In 2002, he collaborated with Bruno Latour and others on the exhibition Iconoclash: Beyond the Image Wars at the Center for Art and Media in Karlsruhe.
His books include Die Suche nach dem Labyrinth--Der Mythos von Daedalus und Ikarus (1983), Caspar David Friedrich and the Subject of Landscape (1990), The Moment of Self-Portraiture in German Renaissance Art (1993), and The Reformation of the Image (2004). Koerner wrote and presented the three-part series Northern Renaissance for BBC Television, as well as the feature-length documentary Vienna: City of Dreams, premiered on the BBC in December 2007.
Koerner was awarded the Jan Mitchell Prize for the History of Art in 1992. He is a member of the American Academy of Arts and Sciences (since 1995) and the American Philosophical Society (since 2008). He is currently a Senior Fellow at Harvard's Society of Fellows.