In the 1960s, in Montreal, while Kate was studying chemical engineering at McGill University and Anna art at the École des beaux-arts de Montréal, they began performing in public and writing their own songs.

From 1963 to 1967 they teamed up with Jack Nissenson and Peter Weldon to form the folk group Mountain City Four.

Their songs have been covered by a variety of artists including Linda Ronstadt,[1] Emmylou Harris,[1] Judy Collins,[1] and others.

They continued to write, record and perform music into the 21st century, with assorted accompanying artists including Gerry Conway, Pat Donaldson, Ken Pearson, Michel Pépin, Chaim Tannenbaum and Joel Zifkin.

[8][9] Anna McGarrigle was married to Canadian journalist and author Dane Lanken until his death on March 3, 2023.

Another sister, Jane McGarrigle (1941–2025), was a film and television composer who acted as business manager for Kate and Anna, and also wrote and performed several songs with the duo.

[3]: 114 They were appointed Members of the Order of Canada in 1993 and received the Governor General's Performing Arts Award in 2004.