Munhall's first appointment was as Assistant Curator of Prints and Drawings at the Yale University Art Gallery. In 1964, he became an assistant professor in the Department of Art History at the university. A year later, he joined The Frick Collection as its first curator, a position he held until 1999. From 1972-1973, he also served as Acting Director of the Collection. In addition to his curatorial work, he continued to teach: he was the Clark Visiting Professor at Williams College in 1974 and served as an adjunct professor at Columbia University from 1979-1981. Munhall was also the corresponding editor of DU: Kulturelle Monatsschrift from 1980-1984. During the thirty-five years that Munhall served as Curator at The Frick Collection, the institution produced the first multi-volume catalog of its holdings and began mounting special exhibitions on a regular basis. Munhall also contributed to a series of major acquisitions, including paintings by Gentile da Fabriano, Hans Memling, and François-Hubert Drouais. He also was instrumental in the acquisition of a significant collection of clocks and watches bequeathed to the museum in 1999 by Winthrop Kellogg Edey.
Exhibitions
Munhall organized or contributed to twenty-eight exhibitions mounted at The Frick Collection and other institutions, including: "Jean-Baptiste Greuze, 1725-1805", the first exhibition to focus on that artist; "Severo Calzetta called Severo da Ravenna" ; "Jean-Antoine Houdon: Eight Portrait Busts" ; "Ingres and the Comtesse d'Haussonville" ; "François-Marius Granet: Watercolors from the Musée Granet at Aix-en-Provence" ; "Nicolas Lancret" ; "The Butterfly and the Bat: Whistler and Montesquiou" ; "Sir John Soane: Collector and Connoisseur" ; and "Victorian Fairy Painting". After his official retirement in 1999, Munhall curated "Greuze the Draftsman" for The Frick Collection, the first show devoted to the artist's drawings. Munhall's drawings and sketchbooks were the subject of an exhibition held at the Frick Art Reference Libraryin the summer of 2002.
Selected honors
Munhall was awarded a Distinguished Achievement Award of the Graduate Alumni Association of the Graduate School of Arts and Sciences at New York University in 1980. In 1989, he was named Chevalier, Ordre des Arts et des Lettres, by the French Minister of Culture for his significant contributions to the understanding and appreciation of French culture. He was named an Officier of the same order in 2001. He was also an Honorary Fellow of The Frick Collection and a Distinguished Scholar in Residence at the Frick Art Reference Library. Munhall is recognized internationally as an authority on the art of Jean-Baptiste Greuze.
Selected publications
Jean-Baptiste Greuze, 1725-1805, 1976
Ingres and the Comtesse d'Haussonville, 1985; reissued 1998
The Butterfly and the Bat: Whistler and Montesquiou, 1995
The Frick Collection: A Tour, 1999
Greuze the Draftsman, 2002
Personal life
Munhall's partner of thirty-nine years was the film historian Richard Barsam.