Omission training is a method in behaviorism used to stop undesirable behaviors. Omission training is when something the subject (the person/animal being trained) enjoys is taken away as punishment for an action or behavior. This is done in hopes to prevent the action/behavior from occurring again. The omission of a reward or something pleasurable will decrease the likelihood of the undesirable behavior occurring again.
For example, if a high school student got a speeding ticket (undesirable behavior) their parents might take away their driving privileges. Not wanting to lose driving privileges again the student will drive slowly to avoid getting another ticket.
Another example would be not allowing a child to play video games for a week because their grades at school were bad. The child will try to improve their grades so that their video games are not taken away again.