If you've trained your dog with one frizbee, for a long time, make sure you have toys that aren't the same color as the frizbee. The reason is that if you've trained it with a red frizbee and throw a red rubber bone in your house or in the park, just to relieve it's stress, it'll pick it up and give it to you. The other thing is that you have to keep training it with one frizbee, otherwise it'll just forget its training with the last frizbee. If you've trained it well it'll always bring the frizbee back.