V–IV–I turnaround

In music, the V–IV–I turnaround, or blues turnaround, is one of several cadential patterns traditionally found in the twelve-bar blues, and commonly found in rock and roll.

The cadence moves from the tonic to dominant, to subdominant, and back to the tonic. "In a blues in A, the turnaround will consist of the chords E⁷, D⁷, A⁷, E⁷ [V–IV–I–V]." V may be used in the last measure rather than I since, "nearly all blues tunes have more than one chorus (occurrence of the 12-bar progression), the turnaround (last four bars) usually ends on V, which makes us feel like we need to hear I again, thus bringing us around to the top (beginning) of the form again.".