V–IV–I turnaround

In music, the V-IV-I turnaround or blues turnaround is a turnaround, or cadential chord progression, named for its use at the end of the twelve-bar blues. It goes: I-V-IV-I, or from the tonic to dominant, to subdominant, and back to the tonic.

The use of the progression from the dominant to the subdominant as a cadence is characteristic of the blues and the twelve-bar blues.

The blues turnaround originated in ragtime, the earliest example being I-I7-IV-iv-I (in C: C-C7-F-Fm-C), "The Japanese Grand March"^[1].

Tonicization and modulation

The twelve bar blues turnaround considered tonally inadmissible^{[citation needed]}, may be interpreted as a doubled plagal cadence^{[citation needed]}:

C     G     F      C
I     V     IV     I
IV/V  V     IV/I   I

In this analysis the first C is an example of a secondary chord.^{[citation needed]}

^ Baker, Duck (2004). Duck Baker's Fingerstyle Blues Guitar 101, p.17. ISBN 0786672102.