When I've had surgery in the past, I've had the doctors ask me at pre-op which side is going to be worked on, and then use a Sharpie (or something similar) to i

When I've had surgery in the past, I've had the doctors ask me at pre-op which side is going to be worked on, and then use a Sharpie (or something similar) to immediately write on my body where they were going to be doing the procedure. So, at least for some doctors, this seems to be standard procedure.