Last Friday I was shooting a parent's night for a local football team. I was the official photographer on the field. Parent's nights are very hectic and usually start late. The shoot has to been done very fast because if the game doesn't start on time the home team will be penalized. at any rate the shoot was going along smoothly until I noticed a another photographer literally standing right next to me shooting over my shoulder. she was so clos to me she was almost Parent's became confused and didn't know who to look at so I finally had to pull my assistant off the line and stood her next to me in an attempt to block the other photographers shot. this caused the photographer to have to move away from me but she stayed as close to my assistant as possible. Parent's didn't know who to look at and most couldn't hear me yelling at them to look at me. As a result, I got parents looking away in many of the shots. I didn't say anything to the photographer at the time because I didn't know if she was a yearbook student ,teacher, newspaper photographer etc who may have had permission to be there. After the shoot, I pointed out the person to the organizer and explained what had happened. She took off to go talk to the person and wasn't happy. I don't know what the result was. Anyway, my question is how to handle that situation in the future? Has this ever happened to any one of you and how do you handle it? What is the etiquette in a situation like this?