In 2001 an international collaboration began with the organist Ignace Michiels, bringing together an almost equal number of singers from Flanders and the Rhein-Main Region to perform an annual concert both in Germany and Belgium.

1990 On 1 November 1990 the choir sang in St. Bonifatius Reger's motets Der Mensch lebt und bestehet and Nachtlied from Acht geistliche Gesänge, op.

1992 On 16 June 1992, commemorating the 80th birthday of Maurice Duruflé, the choir sang in St. Bonifatius his Requiem in the organ version, with alto Laetitia Henke-Cropp and organist Petra Morath.

1998 On 11 January 1998 the choir sang secular choral music in the hall of St. Bonifatius, accompanied by Petra Kristen, piano: Edward Elgar's From the Bavarian Highlands op.

27, the first of "Two Songs to be sung of a summer night on the water" by Frederick Delius, Rutter's Five Childhood Lyrics, and the Zigeunerlieder, op.

The songs of Rutter were performed also on 24 January at a workshop for choral conductors which the composer conducted in Limburg, introducing his Magnificat.

the choral part of the program was William Lloyd Webber's Missa Sanctae Mariae Magdalenae, Jules Van Nuffel's psalm Dominus regnavit, and again Reger's Requiem.

[4] 2002 The choir sang concerts in St. Salvator and St. Bonifatius, the choral part of the program was Joseph Ryelandt's Missa quatuor vocibus mixtis cum organo op.

[5] 2007 As part of the Boni-Musikwochen 2007 in St. Bonifatius, celebrating Das Jahr des Historizismus, the choir sang on 15 Juli 2007 Ryelandt's Missa six vocibus op.

2009 As part of the Boni-Musikwochen 2009 in St. Bonifatius the choir performed choral music from North America, Rupert Lang's Earth teach me on words of the Ute people, Morten Lauridsen's O magnum mysterium, Eric Whitacre's Lux Aurumque, and Moses Hogan's Elijah Rock and Joshua Fit the Battle of Jericho.

2010 Celebrating 25 years, the choir performed as part of the Boni-Musikwochen 2010 in St. Bonifatius the last movement of Bach's congratulatory cantata BWV 134a, Van Nuffel's In convertendo Dominus, the Gloria from Ryelandt's Missa op.

Ignace Michiels began the concert with an organ version of Mendelssohn's Variations sérieuses and an arrangement of Liszt's St. François de Paule marchant sur les flots from Deux légendes (1862).

The choir also sang two works by Belgian composers, Van Nuffels psalm setting Laetatus sum and Joseph Ryelandt's Panem de coelo.

Michiels performed in the concert on 5 November on the Forrest [nl] organ also works by Guilmant, Dupré, Dubois and Widor.