Karen regularly sings with the world’s leading orchestras and conductors including Donald Runnicles, Yannick Nézet-Séguin, Bernard Haitink and Sir Simon Rattle. On the opera stage she performs at Royal Opera, Covent Garden; Metropolitan Opera, New York; Deutsche Oper Berlin; Glyndebourne Festival and Edinburgh Festival.

​Karen was awarded an Honorary Doctorate from the Royal Conservatoire of Scotland. She is also Patron of the National Girls’ Choir of Scotland.