The Canada Revenue Agency ("CRA") recently reversed its long standing administrative policy regarding the exempt nature of nursing staffing agencies, taking the position that these services are taxable and not exempt: see Excise and GST/HST News No. 89 (issued without much fanfare in late Summer 2013).
This effectively decision has effectively reversed the CRA's twenty year old position in GST Memorandum 300-4-2 (Health Care Services, September, 17, 1993) which had previously concluded that these services were all exempt, under section 6 of Part II of Schedule V of the Excise Tax Act.