What do you do, when she doesn't come? And what do you do when she does come?

If you are familiar with the science of behaviorism, you'll know:
1) all creatures do what is in ther own best interest
2) behaviors that are rewarded are repeated, behaviors that are punished are not (Thorndike)

Rewards are anything that the subject finds rewarding (not the handler). Punishers are anything the subject finds punishing (not the handler)

If you're outside and the dog has the choice between coming to you and sniffing another dogs bum, is it in the dog's best interest to come to you? Is it rewarding or punishing to come to you?

Reward based training is based upon the precept, that we want a dog that WANTS to co-operate with us, not one that is forced to. So we ask ourselves, what can we do, so that our dog wants to come when we call?
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Please note: I live in Switzerland, so I'm not selling my services. I would however recommend, you find a good Force Free Trainer who can answer you questions more individually and show you how to reach your training goals and great relationship you got your dog to enjoy. You can do so through the Pet Professional Guild here: *edit*

I would also suggest you read the following book by Alexandra Horowitz "Inside of a Dog" which will dispel some more myths such as pack structure, dominance, alpha and the rest.

Happy Training!

Buzz Cecil