"Within You Without You" is a song by the English rock band The Beatles from their 1967 album Sgt. Pepper's Lonely Hearts Club Band. Written by lead guitarist George Harrison, it was his second composition in the Indian classical style, after "Love You To", and inspired by his stay in India in late 1966 with his mentor and sitar teacher Ravi Shankar. Recorded in London without the other Beatles, it features Indian instrumentation such as sitar, tambura, dilruba and tabla, and was performed by Harrison and members of the Asian Music Circle. The recording marked a significant departure from the Beatles' previous work; musically, it evokes the Indian devotional tradition, while the overtly spiritual quality of the lyrics reflects Harrison's absorption in Hindu philosophy and the teachings of the Vedas.

The song was Harrison's only composition on Sgt. Pepper, although his endorsement of Indian culture was further reflected in the inclusion of yogis such as Paramahansa Yogananda among the crowd depicted on the album's cover. With the worldwide success of the album, "Within You Without You" presented Indian classical music to a new audience in the West and contributed to the genre's peak in international popularity. It also influenced the philosophical direction of many of Harrison's peers during an era of utopian idealism marked by the Summer of Love. The song has traditionally received a varied response from music critics, some of whom find it lacklustre and pretentious, while others admire its musical authenticity and consider its message to be the most meaningful on Sgt. Pepper. Writing for Rolling Stone, David Fricke described the track as "at once beautiful and severe, a magnetic sermon about materialism and communal responsibility in the middle of a record devoted to gentle Technicolor anarchy".

For the Beatles' 2006 remix album Love, the song was mixed with the John Lennon-written "Tomorrow Never Knows", creating what some reviewers consider to be that project's most successful mashup. Sonic Youth, Rainer Ptacek, Oasis, Patti Smith, Cheap Trick and the Flaming Lips are among the artists who have covered "Within You Without You".

George Harrison began writing "Within You Without You" in early 1967 while at the house of musician and artist Klaus Voormann, in the north London suburb of Hampstead. Harrison's immediate inspiration for the song came from a conversation they had shared over dinner about the metaphysical space that prevents individuals from recognising the natural forces uniting the world. Following this discussion, Harrison worked out the song's melody on a harmonium and came up with the opening line: "We were talking about the space between us all".

The song was Harrison's second composition to be explicitly influenced by Indian classical music, after "Love You To", which featured Indian instruments such as sitar, tabla and tambura. Since recording the latter track for the Beatles' Revolver in April 1966, Harrison had continued to look outside his role as the band's lead guitarist, further immersing himself in studying the sitar, partly under the tutelage of master sitarist Ravi Shankar. Harrison said that the tune for "Within You Without You" came about through his regularly performing musical exercises known as sargam, which use the same scales as those found in Indian ragas.

"Within You Without You" is the first of Harrison's many songs to include Hindu spiritual concepts in his lyrics. Having incorporated elements of Eastern philosophy in "Love You To", Harrison became fascinated by ancient Hindu teachings after he and his wife, Pattie Boyd, visited Shankar in India in September–October 1966. Intent on mastering the sitar, Harrison first joined other students of Shankar's in Bombay, until local fans and the press learned of his arrival. Harrison, Boyd, Shankar and the latter's partner, Kamala Chakravarty, then relocated to a houseboat on Dal Lake in Srinagar, Kashmir. There, Harrison received personal tuition from Shankar while absorbing religious texts such as Paramahansa Yogananda's Autobiography of a Yogi and Swami Vivekananda's Raja Yoga. This period coincided with his introduction to meditation and, during their visit to Vrindavan, he witnessed communal chanting for the first time.

Harrison and Boyd returned to England on 22 October, and continued to adhere to a Hindu-aligned lifestyle of yoga, meditation and vegetarianism at their home in Esher. The education Harrison received in India, particularly regarding the illusory nature of the material world, resonated with his experiences with the hallucinogenic drug LSD (commonly known as "acid"), and informed his lyrics to "Within You Without You". Having considered leaving the Beatles after the completion of their third US tour, on 29 August 1966, he instead gained a philosophical perspective on the effects of the band's international fame. He later attributed "Within You Without You" to his having "fallen under the spell of the country" after experiencing the "pure essence of India" through Shankar's guidance.

"Within You Without You" was a song that I wrote based upon a piece of music of Ravi [Shankar]'s that he'd recorded for All-India Radio. It was a very long piece – maybe thirty or forty minutes ... I wrote a mini version of it, using sounds similar to those I'd discovered on his piece.