Richard Bandler and John Grinder put together a technology, based mostly on the modeling work of Richard Bandler . And the earliest modeling of anyone was of Fritz Perls and Virginia Satir. Fritz Perls was a Gestalt therapist and Virginia Satir a family therapist. And so, the first two people that Richard Bandler came in contact with, purely out of convenience based on work Richard was doing with a publisher, were therapists. Later on came Milton Erickson, and then many others.
Early on, Richard and John realized that the technology could be used in many applications, as it is a meta discipline!
Now, after many years, and with many arguments about NLP, let's make a few distinctions about the technology.