His exhibitions include The Drawing Center, Documenta 5, Whitney Biennial, the Jason McCoy Gallery, Robert Miller Gallery, and O.K. Harris Gallery in New York, as well as the San Francisco Museum of Modern Art, the Pennsylvania Academy of Fine Arts, the Akron Art Museum, the Philbrook Art Center, and the Art Institute of Chicago. Posen’s work is in the collections of the Guggenheim, the Pennsylvania Academy of Fine Art, J.P. Morgan Chase, J.B. Speed Museum in Louisville, and the Virginia Museum of Fine Art, among others.