This panel first reviews the literature that demonstrates the efficacy of Positive ABA Behavior Supports in addressing the most severe and challenging behavior. Additional Type III case studies are then presented that add to this evidence base. The target behaviors addressed include severe physical aggression, self-injury, and property destruction. In each case, behavior problems were brought under control, both in terms of occurrence and episodic severity. Each person's quality of life was also measureably improved. These results were achieved through the implementation of positive, multi-element behavior support plans based on comprehensive functional assessments. Further, the results have been lasting, indicating the generalization of treatment effects over time. Finally, given the existing and growing evidence of PBS efficacy, a number of explanations are offered as to the challenges Positive Behavior Supports continue to face. An important perspective for Behavior Analysts is to recognize is that if a positive ABA approach is equally or more effective than an aversive approach, ethics require the use of the less restrictive alternative.