Ontario Hospital Association was created in 1924.
Ontario Library Association was created in 1900.
Ontario Soccer Association was created in 1901.
Ontario Nurses' Association was created in 1973.
Ontario Dental Association was created in 1867.
Ontario Sustainable Energy Association was created in 2001.
Ontario Association of Food Banks was created in 1992.
Ontario Association of Career Colleges was created in 1973.
Ontario Co-operative Association was created in 2002.
Ontario English Catholic Teachers' Association was created in 1943.
Nigerian Medical Association was created in 1951.
Aerospace Medical Association was created in 1929.