There is nothing like the thrill of running behind a dog that is hot on the scent of a lost child, or the adrenaline rush of the handler of a police dog tracking a suspected criminal hiding in a neighborhood. But to reach that point where the dog knows what to do, and the handler trusts him to do his job, requires many practice tracks, in varying weather and varying lengths and conditions. A dog needs approximately one hundred training sessions before testing should be done. This means that the handler should give his dog a solid foundation. Without some way to record these training sessions, it can be difficult to know when a dog is ready to be tested.