Summer's Last Will and Testament is a choral masque or cantata by Constant Lambert, written between 1932 and 1935, and premiered in 1936. It is scored for chorus and orchestra, with a baritone solo also featured in the last of its seven movements. It is based on the play of the same name by Thomas Nashe, written around 1592. Lambert considered the work his magnum opus, and it is his largest work in any genre. However, it attracted little attention at its 1936 premiere and had only one or two other performances in Lambert's lifetime (he died in 1951).