hilberry became assistant director of the metallurgical laboratory in 1943. on july 1, 1946, the metallurgical laboratory became argonne national laboratory, the first designated national laboratory, with walter zinn as director, and hilberry as associate director. he became the deputy director in 1949, and the director in june 1956, on zinn's departure. he was the first director of argonne's international school of nuclear science and engineering, an important part of the eisenhower administration's atoms for peace program, from 1955 to 1956. he stepped down in november 1961, and was replaced by albert crewe. he remained at argonne as a senior scientist until 1964, when he accepted an appointment as professor of nuclear engineering at the university of arizona. he retired and became a professor emeritus in 1985.