Pétur Grétarsson studied music at the Reykjavik Conservatory and later at Berklee College of Music in Boston. Freelancing musician since 1985. Regular stints with the Iceland Symphony. Instructor in theory, percussion, ensemble, creative listening and event management at the FIH Music School. Founding member of the Benda Percussion Group 1998. Extensive experience as performer and composer at the Reykjavik City Theatre and the National Theatre. Manager of the Icelandic Music Awards 2006-2011. Artistic and managing director of the Reykjavik Jazz Festival 2007-2014.

Music Producer for Rúv (Icelandic Broadcasting Service) since 1987 focusing on cross-genre music programming. Receiver of the 2018 Icelandic Music Day honour for music in the media.