Raison D'etre is Peter Andersson's best-known music project. Formed in 1991, Raison was used as a tool of expression, with the ultimate goal being one of self-realization. Over the decade, Andersson assembled several tapes and eight CD releases of dark ambient industrial landscapes that combine opposite sides of the mood spectrum. Haunting, eerie, dark and foreboding electronically created soundscapes and sound collages, crafted using all the electronic tools of the trade, including deep, thunderous and distant percussion, Gregorian chants, choirs, samples and effects that add subtle intensity to the finished pieces. The discography consists of Aprés nous le Déluge (1992), Prospectus (1993),Enthralled By The Wind... (1994), The Ring of Isvarah tape, Depths of Silence and Phormations, In Sadness, Silence & Solitude (1997), Prospectus I (1997), Reflections From The Time Of Opening MCMXCI (1997), Within Depths (1998), Absolute Supper (2CD; 1998; 135 Mins. unreleased CMI tracks), Perception Multiplied (Peter Aandersson Collection; 1998), Collective Archives (2CD; 1999), The Empty Hollow Unfolds (2000), Lost Fragments (2002) and Requiem For Abandoned Souls (2003).