Among other roles with the Royal Opera, she has sung Alice Ford (Falstaff), Santuzza (Cavalleria rusticana), Ellen Orford in Peter Grimes, Leonore (Fidelio) and the Old Countess (The Queen of Spades).
She also appeared in the world premières of two operas by Sir Michael Tippett: The Knot Garden (as Denise) and The Ice Break (as Gayle).
[clarification needed] Rehearsals for Salome and an interview with Barstow were featured in a December 1975 episode of the BBC television programme Arena.
Also for Opera North in 2021 (revived 2022) she sang, and spoke, the role of Madame Armfeldt in A Little Night Music by Stephen Sondheim.
She danced a choreography by Mark Morris, wearing a costume designed by Sarah Nash Gates, involving the literal removal of seven veils.