The Pro's outweigh the cons in my opinion..but here are some: Shifts can get cancelled on you anytime, even if you picked up the shift months in advance, and you wont get paid for it unless it's within 24 hrs of the shift when the cancellation occurs. So then you might be left without work/compensation on occasion. The type of person who does relief needs to be ok with this aspect. They need to be ok with uncertainty, always flexible, changing clinics regularly- not a lot of shifts in the winter. May need to be willing to drive farther for some jobs.