raison d'être (French for "reason to be") is a dark ambient project from Boxholm, Sweden, whose sole member has always been Peter Andersson. Formed in 1991 as a tool of expression with the goal of self-realization and deeper knowledge of the inner Self. The music produced by raison d'être is chiefly dreamlike dark ambientsoundscapes, with industrial touches. For example, synthesizers might play a droning melody over the sounds of metal on metal. Andersson often mixes Gregorian chants with his own keyboard and percussion playing.