We have "unleashed" but unfenced dog parks, which do absolutely no good when it comes to dogs who have a tendency to roam. 
 
 
But, as bobodiddle suggested, we use fenced softball fields. I've helped organize a group of about 10-15 dog owners who meet at the same time every Sunday. It has worked out great. You just have to make sure you clean up after your dogs to avoid getting league officials mad at you. 
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 Mike ~ Doting Dad to Jillie, Harper, Molly, Cooper, Eddie (RIP), Lucy (RIP), Rusty (RIP) and Jack (RIP). 
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