OK - thanks guys! As I have never freedived (except for the 5 meters to the bottom of the swimming pool etc) I have always thought as a buddy in the scuba sense - i.e. someone with another air supply! I didn't really see that in connection to free diving. I suppose what is being called a buddy in free diving here is what I'd usually think of as a safety diver. I must say that because of SWB etc, I don't think I'd ever want to do that on my own!!! (although I will solo scuba at very shallow depths!)