Alwynne Pritchard explores the world of improvisation and its role in contemporary classical music, in a discussion with composer Richard Barrett and writer John L Walters. The programme includes a recorded studio session by Elliott Sharp and Christian Marclay. Sharp/Marclay: Improvisation Elliott Sharp (guitar, soprano saxophone, electronics) Christian Marclay (turntables, electronics) Barrett: Adrift Sarah Nicolls (piano) Richard Barrett (electronics) Tchaikovsky, arr. Oswald: Violin Concerto Jon Rose (violin) BBC Scottish Symphony Orchestra Ilan Volkov (conductor) Bailey, arr. Burn: Three Rhodri Davies (harp) Angharad Davies (violin) Nikos Veliotis (cello).