The Choir of Saint Peter in Chains Cathedral provides musical leadership primarily at the 11:00 Sunday Mass (mid September through mid June), Christmas and Holy Week and at special archdiocesan events. The choir, made up of some 18 - 24 professional singers, provides a wide range of liturgical choral music of all periods of the church's tradition from Gregorian chant through the 21st century. The choir also sings an annual Advent Service of Lessons and Carols on the first Sunday of Advent and the Tenebrae service the Wednesday evening of Holy Week.  Concerts are presented each year often with orchestra as part of the Great Music in a Great Space. Over the past several years the Choir has collaborated with the KSO on several programs — "Touched by an Angel" (Gabrieli and Arnesen), "Via Doloroso" (Higdon and Łukaszewski) and Mozart’s Denuoument (Requiem). Membership in the cathedral choir is open to trained singers through audition.