"One Way Out" is a blues song first recorded and released in the early-mid-1960s by Sonny Boy Williamson II and Elmore James, an R&B hit under a different name for G.L. Crockett (who also recorded as "G. Davy Crockett") in the mid-1960s, and then popularized to rock audiences in the early 1970s and onward by The Allman Brothers Band.

As with many blues songs, the history of "One Way Out" falls into murk. It seems to have been originally recorded by Elmore James at Beltone Studios in New York City in late 1960 or early 1961, as part of James' Fire/Fury/Enjoy recording sessions. It features a full band arrangement with a four-piece horn section, but a completely different melody from later versions. James appears not to have released it at that time.

Instead, Sonny Boy Williamson II reworked and recorded it for Chess Records in Chicago in September 1961, releasing it shortly thereafter. He would then return and re-record a different working of it in September 1963, again for Chess in Chicago, this time with Buddy Guy on guitar and Lafayette Leake on piano. The two efforts were substantially different, with one dominated by harmonica playing while the other has the vamp and arrangement that would become familiar with the Allman Brothers' rendition.

Subsequently, the initial Elmore James version of "One Way Out" was posthumously released in 1965, using it as the B-side of his single "My Bleeding Heart" for Sphere Sound Records. But by now, the song was associated with Sonny Boy not him.

Writing credits for "One Way Out" have varied over the years, with some recordings crediting Sonny Boy alone, then others giving Marshall Sehorn and Elmore James the nod, and finally some naming all three. Furthermore, Sehorn was a recording engineer, record producer, and all-around "record man" at Fire/Fury Records in New York, who likely engaged in the then-common practice of adding himself onto composer credits of songs that he was not actually involved in writing, to get a cut of subsequent royalties. And of course no confusion is complete without mentioning that there are two different Sonny Boy Williamsons − I and II; "One Way Out" pertains to the second one.

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