Who Should You Allow Into Your Horse's World?

Horses live for freedom, friends and food. As horse lovers and parents it is our responsibility to ensure that our horses' lives include these. What we can hope for in return is a relationship of some kind, but all we can expect is the satisfaction of being a good parent.
Horses won't recognize the effort we put into ensuring they're fed properly, provided with adequate space to move freely, how we ensure their safety, resources we put into maintaining their health or the thought we put into allowing them to safely socialize. However, they can feel the positive outcome of our efforts. They can also read the feeling of a moment or event, and they remember the association between feelings, events and who was present.
Therefore, if you want to promote a strong and positive relationship with your horse, it is important to not only provide freedom, food and friends but to do so in a way that associates you, in the mind of your horse, with all the good things in live.
This, maybe most especially, includes who else you allow in your horses' lives; trainers, vets, dentists, farriers. Allow only people that can provide a positive experience and positive outcome. Compromising one for the other will undermine your reputation with the horse.
Lastly, keep in mind that a horse is not going to perceive a warm hug from a loud and friendly stranger like we might, and certainly not in a positive way. Align your comfort with the events of a trim, or other activity, with your horse's comfort. And, remember the horse will do the same, so you both need to strive to be comfortable with each situation.