Clicker training is very useful for marking the exact time that the required behaviour has occurred. You have to get your timing right though or you might mark the wrong behaviour. I use this method for training tricks and for preparing dance moves. For walking on the lead, I just turned in the opposite direction when the dog pulled. It took a while but happened without any punishment of behaviour. I prefer to deflect behaviour, rather than to punish it. To my way of thinking, if you engage your dog's mind, you don't "usually" get bad behaviour. One forum member mentioned Cesar. I agree with his method of always encouraging owners to walk their dogs. We do this and also give them plenty of off leash freedom, having taught recall with the aid of hide and seek games round trees. So from this you can see we use whatever works at the time.