Can recommend a few, all Monty Roberts Recommended Associates (RA's). I've used RA's in the past for loading issues etc and they have been brilliant, completely non violent and long lasting solutions!
Thats great thankyou very much for all these links this is going to be of real help as i have not yet managed to completely solve all my horses issues so this is making my new year more hopeful. Thanks very much!
My horse used to be awful in traffic until i moved him to a yard where his stable overlooked the carpark (so there were cars and tractors, lorries etc driving past slowly throughout the day. This made him a million times better! Don't know if it would work for your horse but might be worth a try? (I had tried loads of things previously, nothing worked!)