Sector- Specific Information (Ex: agriculture, arts, science, trades)
http://www.councils.org/careers/

Regulated Professions in Ontario (Ex: physicians, nurses, lawyers )
http://www.ontarioimmigration.ca/en/working/OI_HOW_WORK_PROF_PROFS.html

National Occupation Classification (NOC)
http://www5.hrsdc.gc.ca/noc/english/noc/2006/AboutNOC.aspx