"Sgt. Pepper's Lonely Hearts Club Band" is a song written by Paul McCartney, credited to Lennon–McCartney, released in 1967 on the album of the same name by the Beatles. The song appears twice on the album: as the opening track, and as "Sgt. Pepper's Lonely Hearts Club Band (Reprise)", the penultimate track. As the title song, the lyrics introduce the fictional band that performs on the album.

Sir James Paul McCartney is an English singer, songwriter and musician who gained worldwide fame with the Beatles, for whom he played bass guitar and shared primary songwriting and lead vocal duties with John Lennon. One of the most successful composers and performers of all time, McCartney is known for his melodic approach to bass-playing, versatile and wide tenor vocal range, and musical eclecticism, exploring genres ranging from pre–rock and roll pop to classical, ballads, and electronica. His songwriting partnership with Lennon is the most successful in modern music history.