Deborah was Associate Chorus Master from 1999 - 2012. During this time she prepared many works for them including Mahler 2 & 8, Verdi Requiem, Bruckner Mass, Berlioz Requiem and the Missa Solemnis for various conductors including Sir Colin Davis, Sir Simon Rattle and Valery Gergiev. She also prepared lighter programmes - in concert with Lesley Garrett and Classic Spectaculars at the Royal Albert Hall.
Deborah toured with them to Montepulciano and Bologna for four performances of the Mozart Requiem. She also prepared the music for the recording of the successful television series Merlin with music by Rob Lane (photo below). She still maintains an association with them and takes an occasional rehearsal.