Normally, yes. Whenever we go into town or whatever, we always put a leash on the dogs. But if we are out in the backyard, no...it is fenced, so go figure. If we are just going for a walk around the neighborhood where there are not many cars or too many people, I'll always start with them on leashes and if they are acting well-behaved I'll take their leashes off but keep them in my hands just in case something happens. Usually, if I plan on taking a walk off-leash, I'll try to just go with one of the dogs at a time. The two of them can be quite a handful.