Dear joejoe, horses do not think like people and try to get even when they are not permitted to do what they feel they need to do. They simply respond to stressful requests ie; holding him back, by stressfully dealing with their options. He was feeling trapped and it came out by going sideways and bucking. He obviously had some pent up energy that he needed to release. The pent up energy was caused by his inability to do what he was trained to do…be first. My ottb would do this on trail rides with more than 2 other horses if he was expected to be 3rd (last). It was up to me to figure it all out. I decided to begin the trail ride with him in the lead. When he became more relaxed, I would ask the other rider to walk past him and lead for 3 strides then pet him and return him in the lead for 5 strides. Then other horse would lead for at least 5 strides then get back behind. I would only do this after we were out for a while and he was really relaxed. This process cannot be rushed. We must read their body language and only do it when they are not stressed. It is the horse that tells the rider when they are open to relaxation. It is only then that they can trust the new and different way of going. Flight animals cannot relax because we scold them, spur them, or stress them with a whip. Some horses may shut down with these methods but it is very stressful to them which is why many of them give up and do exactly what we want. Lets hope they have ulcer medication too! Please consider only small classes or better yet, solo classes at these “fun” shows and ask yourself if they are fun for your 20 something Arab!