He is particularly known for his widely used choral arrangements of Christmas carols, many of which were originally written or arranged for the Service of Nine Lessons and Carols at King's and/or the Bach Choir's Christmas concerts. They are published in the five "Carols for Choirs" anthologies (1961–1987), edited by Willcocks with Reginald Jacques (first volume) or John Rutter. The descant arrangements in particular are among the most famous and well-loved musical components. He was Music Director Emeritus of King's College Choir, and an Honorary Fellow of King's College, Cambridge.