Trying to get the sympathy vote by focussing on doctors is not appropriate. There are all sorts of people who are employees by all labour regulation definitions but choose to incorporate to take advantage of all sorts of tax deductions in addition to the income splitting (cars as a capital deduction, portion of residence, trips, conferences, etc). Then when you finally end up 'paying yourself' you do the rrsp, etc. Almost every work sector has someone doing it. The increase in the number of corporations is not just the health sector.