Arnold Olaf Sundgaard (1909–2006) was an American playwright, librettist, and lyricist. He was also a writer of short stories and children's books as well as a college professor specializing in drama and theatrics.
Sundgaard was best known for his role in the production of six Broadway plays. Sundgaard wrote the libretti for close to a dozen operas and musicals by composers such as Alec Wilder, Douglas Moore, and Kurt Weill.
With Moore he wrote the opera Giants in the Earth, it won the Pulitzer Prize for Music in 1951. In 1952 he wrote The Lowland Sea with Wilder. In 1948 he and Weill collaborated on the folk opera Down in the Valley. With Victor Ziskin he wrote the short-lived The Young Abe Lincoln, which played briefly on Broadway in 1961. S
undgaard was also a lyricist, writing words to several songs by Wilder. "How Lovely is Christmas" was recorded by Bing Crosby; "Where Do You Go?" was recorded by Frank Sinatra and released on his 1959 album No One Cares.
Besides theatrical work, Sundgaard wrote nonfiction for The New Yorker and Atlantic Monthly, among other publications.
