Del Shannon had written "I Go to Pieces" for an R&B singer named Lloyd Brown whom Shannon discovered at a Michigan nightclub. Shannon arranged and produced Brown's recording but was unable to find a label interested in releasing the track. Shannon did attempt to himself record "I Go to Pieces" in the August 1964 session at Mira Sound Studios NYC, which yielded Shannon's single "Do You Wanna Dance" and its B-side "This is All I Have to Give". However Shannon was unable to cut a satisfactory vocal of "I Go to Pieces" before the three hours booked for the session ran out.

Following the success of the Peter and Gordon version of "I Go to Pieces", Del Shannon himself recorded the song at Bell Sound Studio NYC in March 1965. Basing his version on the arrangement utilized by Peter and Gordon, Shannon's version of his own composition was effectively one of a number of covers of recent hits which comprised his album One Thousand Six Hundred Sixty One Seconds with Del Shannon. Shannon also sang on the remake of "I Go to Pieces" by Nils Lofgren on his 1981 album Night Fades Away.

"I Go to Pieces" passed to Peter and Gordon when that duo and Del Shannon along with the Searchers shared the bill for a tour of Australia in the second half of 1964. At one of that tour's venues Shannon pitched "I Go to Pieces" to the Searchers singing it for the group in their dressing room: Peter and Gordon in the dressing room next door overheard Shannon singing "I Go to Pieces" to the Searchers - who weren't interested in it - and recognizing the song's potential to become a Merseybeat-style hit Peter and Gordon asked Shannon to let them record it. Peter and Gordon recorded "I Go to Pieces" at Abbey Road Studios with John Burgess producing and Geoff Love as arranger/conductor; as well as Peter and Gordon themselves playing guitars the session featured [Eddie King], their guitar player/MD, on twelve string guitar. , Released in the UK on 20 November 1964, "I Go to Pieces" became the second consecutive Peter and Gordon single to miss the UK Top 50 but like the preceding "Nobody I Know", despite missing the UK charts it became a hit in the US where the "British Invasion" craze was at its height in 1964-65. Released in the US in December 1964, "I Go to Pieces" entered the Top Ten of the Billboard Hot 100 that February. The title track of Peter and Gordon's third US album release, "I Go to Pieces" was cited in 1999 by Gordon Waller as his favorite of the duo's songs. Peter and Gordon's first three singles had all been Lennon–McCartney compositions; "I Go to Pieces" began a series of four single releases by the duo which were covers of American songs.

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