Pet Sounds is the eleventh studio album by the American rock band the Beach Boys, released on May 16, 1966, by Capitol Records. It was produced, arranged, and primarily composed by Brian Wilson with guest lyricist Tony Asher. Recorded largely between January and April 1966, it furthered the orchestral sound introduced in The Beach Boys Today! (1965). Initially promoted as "the most progressive pop album ever", Pet Sounds is recognized for its ambitious production, sophisticated harmonic structures, and coming of age themes. It is widely regarded as among the greatest and most influential albums in music history.

Wilson viewed Pet Sounds as a solo album and attributed its inspiration partly to marijuana use and an LSD–rooted spiritual awakening. Galvanized by the work of his rivals, he aimed to create "the greatest rock album ever made", surpassing the Beatles' Rubber Soul and extending Phil Spector's Wall of Sound innovations. His orchestrations blended pop, jazz, exotica, classical, and avant-garde elements, combining rock instrumentation with layered vocal harmonies, found sounds, and instruments not normally associated with rock, such as French horn, flutes, Electro-Theremin, bass harmonica, bicycle bells, and string ensembles. Featuring the most complex and challenging instrumental and vocal parts of any Beach Boys album, it was their first in which studio musicians, such as the Wrecking Crew, largely replaced the band on their instruments, and the first time any group had departed from their usual small-ensemble pop/rock band format to create a full-length album that could not be replicated live.