Baillargeon received a classical education at the Ursuline Convent in Quebec City and at the École Sophie-Barat in Montreal.
For several years she participated in writing and performing in its collective creations, which had a marked effect on the theatre of Quebec during the late 1960s and early 1970s.
The Great Ordinary Movie (Le Grand film ordinaire), released in 1971, is a documentary based on its first performance piece.
[3] In 2011, the NFB released her autobiographical work Trente tableaux, an anthology film composed of 30 filmic portraits of her 66 years of life to date, including her experiences as a woman in Quebec's changing society.
[4] She has received Quebec's two highest film honours: the Prix Albert-Tessier in 2009 and the 2012 Jutra Award for lifetime achievement.