[2] He attended The Hill School and then Yale University where he graduated magna cum laude in 1957,[2] played varsity tennis and won the History of Art Prize.
[3] In 1962 he moved back to Washington, DC, where he became a designer with the firm of Keyes, Lethbridge & Condon until he and George Hartman founded Hartman-Cox Architects in 1965.
[5] The firm's work has appeared in major architectural publications and is the subject of two monographs.
Cox's work includes the Brewer House, the Chapel at Mount Vernon College, the National Permanent Building, the addition to and renovations of the Folger Shakespeare Library,[6] the Library and residence hall at the Georgetown University Law Center, the renovations of the National Archives and the Smithsonian Museum of American Art and National Portrait Gallery, the renovation of the concert hall at the Kennedy Center, the Addition to the Kennedy-Warren apartment building, and Sumner Square in Washington, D.C.
[8] He has served on numerous architectural design awards juries and lectured extensively throughout the country.