The dangers of the off-leash park
Did you know that off leash, enclosed dog parks are very dangerous places for your dog? I am not really a fan.
When you have number of dogs running together they will form a pack hierarchy. If a number of those dogs go to the same park often, they will also regard that park as their territory. This can be a recipe for disaster. A newcomer coming into the park can easily be seen as an intruder and become a victim of a dog attack.
I personally think that all dogs that enter and are allowed to run free in a dog park should be shown to be completely under control by their owners. Their recall should be spot on, so that at any hint of trouble all dogs can be called back by their owners.
The reverse of this is actually true, with owners of untrained dogs visiting these parks because they want to let their dogs have a run in an enclosed area, where they won't lose them.