The kid on the skateboard who appears outside Jimmy's window during the first third of the movie when the band are recruiting members is Peter Rowen, the then boy from the covers of U2's "Boy" (1980) and "War" (1983) albums. At the time this movie was filmed, he owned a skate shop in Dublin and was a champion skateboarder.
Johnny Murphy (Joey The Lips) and Bronagh Gallagher (Bernie) were the only ones in the group who had no music experience before making the film.
The producers wanted Andrew Strong's father to audition for one of the roles. He brought his 16-year old son along, who then landed the lead role.
Maria Doyle Kennedy was a member of The Black Velvet Band before the movie was made. She was the only member of The Commitments (the band) with a notable career before the movie.
The Corrs, the highly successful Irish band, got their start by auditioning for the film, and they each won small roles.
- Andrea Corr (lead vocals & tin whistle) plays Jimmy's little sister Sharon.
- Jim Corr (guitar) is part of the Avant-Garde-A-Clue Band.
- Caroline Corr (drums) appears in the audience during the performance of "I Never Loved A Man".
- Finally, Sharon Corr (violin) can be seen playing violin with the country & western band that Bernie joins at the end of the film.
Colm MacConiomare: violinist with Glen Hansard's band The Frames, during the auditions as a young violin player.
Alan Parker: the record producer in the studio near the end of the film. A cardboard cut-out of him can also be seen in the background in a video shop, and cassettes of his films are on the shelves.