The only immediate and completely humane way to teach your dog to stop jumping. All dogs jump on people. It is their way of showing affection and getting attention. Dogs view jumping as an appropriate greeting. We developed a training aid that immediately takes the guesswork out of your attempt to correct and re-direct their behavior. By simply blocking their landing spot, your dog will not jump up. This allows you the opportunity to use your verbal command of "Off", or "Down", simultaneously rewarding him for not jumping, thereby giving him the attention he desires while not allowing him to jump.
 
The alternate training techniques are as follows; 1) Ignore the dog until it stops jumping, and then reward them when they stop. This is NOT an option for the out of control overly rambunctious and dangerous jumpers. It certainly cannot be used on strangers while out on a walk. 2) Squeeze their paws when they jump (this video has nearly 1/2 a million views on YouTube!) The problems with this are obvious -- dogs don't trust you, become afraid of having their paws handled, dogs may bite you for doing it, and it's probably not something you want to ask friends or strangers to do. 3) Step on their leash -- I have never tried this. If I put my dog's leash on, he is expecting to go for a walk. I would not confuse him with this technique as a training method, nor can I comment on how effective it is, except to say that it doesn't seem like a great idea. 4) Squirt them with a spray bottle. I am not a big fan of the spray bottle, but it can have it's place. If the dog responds, it should only be used on a very limited basis. 5) Use canned air with a loud sound -- not something I would do with the type dogs I have worked with. I would never do anything to startle a dog. 6) "Hobble" them with a No Jump harness (two things about this -- 1) if the dog is jumping wildly, how, in the world are you going to get a harness on him? And 2), won't the dog quickly realize that the only time he can't jump is when he is physically restrained?)  7) Tie them up while teaching them command -- useless. 8) When guests come over -- put them in another room, or a crate, or outside, or at put them at someones house while you have company-- yes, I have seen this advice by "professional" dog trainers. 9) Believe it or not, there is a company marketing a "Catch Pole" as a training device!!! This is also on YouTube.10) Use a Prong Collar  and give them a good jerk when they start to jump. Please read this link carefully before attempting this http://barksfromtheguild.wordpress.com/choke-and-prong-collars-health-concerns-call-for-equipment-change-in-dog-training/  Everything above, aside from "ignoring" them, are techniques that cause the dog to develop a "learned helplessness" much like Cesar Milan does by overwhelming the dog with dominance. So, those are the current options.
 
Dogs have a huge range of personalities, and "history", both by breed and past experience. Some are bold and confident, and fairly unflappable, and others are timid and shy, and easily spooked. Not every dog will respond the same way to every technique. If a dog can be taught with the "ignoring" method, I am all for it! But, for a trainer to say that is the end all to teaching a jumper not to jump is doing a grave disservice to dogs and their owners, when that method DOES NOT work for them. When I say does not work, I mean that there are dogs that jump very aggressively, knock people down, scratch them, and simply can not stop the behavior even for a split second, so that you can "reward them" for not jumping. "Down Rover" protects you from the assault, allows you to block the attack, and interrupt the behavior, so that the dog's attention can be redirected to you. This ALLOWS you to reward them far more quickly for the appropriate behavior.