A turnaround is a brief series of harmonies interpolated between two tonic harmonies, for the sake of variety and formal clarity (e.g., to mark a boundary between the concluding tonic of one blues chorus and the initial tonic of the next). A turnaround thus reinforces the home key, rather than moving to another key; in more formal music-theoretic terms, prolonging the tonic rather than progressing elsewhere. Common examples include

 

I–vi–ii–V in jazz

 

and

 

IV–#IV–V in blues.