He is a former professor of music at BYU, where he directed the Men's Chorus and Concert Choir. At BYU he was a member of the American Piano Quartet which included Paul Pollei, himself, and different other pianist at different times (Massimiliano Frani, Del Parkinson, Ronald Staheli, and Douglas Humphreys). This group toured throughout the world and commissioned many original works. Wilberg created many of their arrangements himself. His compositions and arrangements are performed and recorded by choral organizations throughout the world. In addition to the many compositions he has written for the Mormon Tabernacle Choir, his works have been performed by such artists as Renée Fleming, Frederica von Stade, Bryn Terfel, the King’s Singers, Audra McDonald, David Archuleta, Natalie Cole, Brian Stokes Mitchell and narrators Walter Cronkite and Claire Bloom.