Dog Parks are offleash areas whereby your dog can run around and interact with everyone and everything. Most dogs get on well, but not every dog.
Remember this, don't expect your dog to get on with every other dog.
If your dog gets into a play fight, but it then stems to a more aggressive interaction, don't try to break it up with your hand. Your hand will not win the fight if teeth connect with you.
This is very hard not to do, because you want to look after your dog and also stop the fight as you are probably worried other the other owner will get upset or anxious about the situation.
Grab your dog before it brews. Watch your dog all the time when in a dog park, don't just presume that everything is fine and they are all getting along.
Once you have grabbed your dog, settle him/her down and lower the adrenalin thats pumping through the body.
Little dogs, big dogs, different shapes and sizes, will all at some point come across a situation whereby they will feel unsure, intimidated and/or outsized. Keep your dog distracted with a ball, or have your dog well trained, where you can call them off a situation quickly. This is very hard though, and takes lots of work to get your dog trained to that level.
Just keep your wits about you and know when to go to the dog park, know which dogs your dog gets on with and the chances of something going wrong will be less.
Dog parks are wonderful places, however always be careful!
Happy fun at dog parks!