Without a doubt, the most important exercise we can teach our dog is the recall. Getting a dog to generalize the meaning of the "come" starts in Basic Dog Obedience. It continues with recall drills in Intermediate Dog Obedience, and is finished in Advanced Dog Obedience (in the works).
This does not happen in a month or two. In fact, it can take many months for our dog to learn that it has to come no matter what distraction it faces. This is a concept that all the "all-positive" trainers either do not understand or refuse to acknowledge.
This video came directly out of our training DVDs and online courses, Basic Dog Obedience and Intermediate Dog Obedience.