An Ontario Land Surveyor (O.L.S.) is a member of the Association of Ontario Land Surveyors who is authorized under the Surveyors Act to engage in the practice of cadastral surveying in Ontario; is a Land Information Professional licensed by the A.O.L.S.
Source
http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_90r20_e.htm