Brett Fairbairn was born in Winnipeg, Manitoba on April 24, 1959 to Clarence and Eva Fairbairn. Fairbairn grew up in Saskatoon, Saskatchewan, where his father was a reporter and photographer for the Saskatchewan Wheat Pool's Western Producer starting in 1966. Fairbairn received his Bachelor of Arts degree (History, Languages) from the University of Saskatchewan (1981); his Bachelor of Arts Honours (First Class) degree in Modern History from the University of Oxford, England (1983); and his Doctor of Philosophy degree in Modern History from the University of Oxford (1987).

Fairbairn has been involved with the University of Saskatchewan for many years. During his undergraduate program, Fairbairn was president of the University of Saskatchewan Students' Union. From 1986 to 1991, Fairbairn was Assistant Professor in the Department of History (jointly appointed with the Centre for the Study of Co-operatives). He was promoted to Associate Professor in 1991, and to Full Professor in 1996. He served as director of the Centre for the Study of Co-operatives from 2000 to 2004. He served as head of the Department of History from 2004 to 2006 and from 2007 to 2008.

From 1990 to 1991, Fairbairn served as committee secretary and author on the Steering Committee for the Issues and Options Integrated Planning process conducted at the University of Saskatchewan (begun in 1985). From 1995 to 1996, Fairbairn was chair of the Committee to Review the Role and Mandate of the Extension Division. Between 2000 and 2006, Fairbairn was an active member of University Council, including terms as chair of the Council, as chair, vice-chair, and member of the Planning Committee of University Council, and as a member on various sub-committees of the Planning Committee. In 2008, Fairbairn was appointed Provost and Vice-President Academic for the University of Saskatchewan. As of 2010, he continues in this position.

Fairbairn has published widely on co-operation and community development, and was awarded the Queen's Golden Jubilee Medal by the Lieutenant Governor of Saskatchewan in 2002 in recognition of his publications. He is also a consultant in the field of community development and co-operatives, and has worked as a researcher, writer, and trainer on projects with major co-operatives in Saskatchewan and with provincial and federal government agencies. He is an active volunteer in a variety of community and co-operative organizations, and served a term as the president of the Saskatoon Community Clinic.

From 1988 to 1994, Fairbairn was editor of the Canadian Journal of History / Annales canadiennes d'histoire. From 1988 to about 1995, he was involved with policy development within the Saskatchewan New Democratic Party. In 1996, Fairbairn undertook a part-time secondment as a policy advisor to the Ministry of Post-Secondary Education and Skills Training, Government of Saskatchewan. From 1997 to 2004, Fairbairn served on the Saskatchewan Archives Board, including time serving as chair of the Board.

Fairbairn currently (2010) lives in Saskatoon with his wife, Norma. They have three children: Catherine, Elena, and David.