Specialized in documentary filmmaking, Pierre Marier directed several documentaries in Central America, including Paz si, guerra no! (1986), Of Lives Uprooted (1987), The Streets of San Salvador (1991). Over a period of fifteen years, Marier directed television episodes for series which address questions of cultural diversity in contemporary Quebec. Since then, he has dedicated himself mostly to producing independent documentary films for Les films du tricycle : The Legacy of Oka Trappists (2008), Augustinians, Body and Soul (2010), Fighting through the Night (2016) and directed An American, Portrait of Raymond Luc Levasseur (2015).