Harry Edward Nilsson III, sometimes credited as Nilsson, was an American singer-songwriter who reached the peak of his success in the early 1970s. His work is characterized by pioneering vocal overdub experiments, a return to the Great American Songbook, and fusions of Caribbean sounds. Nilsson was one of the few major pop-rock recording artists to achieve significant commercial success without performing major public concerts or touring regularly.

The Great American Songbook is the loosely defined canon of significant 20th-century American jazz standards, popular songs, and show tunes.