I bring my cocker spaniel on solo rides. She's great off the leash, doesn't crap on the trail and will keep up for an hour to ninety minutes before getting tired (albeit at a slower pace than normal). She runs right behind me so I put a small bear-bell on her collar so I know that she's still close. When we meet hikers or other riders on the trail, I cede the way and she'll stay with me without running after anyone else.

I don't bring her with me if I go out with other human beings. She gets a little distracted and those rides are often a quicker pace.

Some of the trails I ride are quite close to new subdivisions. Nearly every ride I'm on I'll pass someone either hiking or riding with a dog.