Since 1998, the introduction of Applied Behavior Analysis (ABA) to the treatment of Autism Spectrum Disorders (ASD) in Ireland has created much excitement, controversy, confusion, and resistance. Much of the controversy and resistance has been generated based on a myriad of misconceptions, and fallacies, about a science of human behavior that has been built on over 80 years of empirical research. This chapter reviews the different methods (and perceptions) of how Behavior Analysis is applied to the treatment of ASD in Ireland: including its use in schools through a Behavior Analytic whole-systems approach; and its use in home-based educational programs. Also, there is a discussion of general 'eclectic' methodological approaches to the education of children with ASD within special and mainstream schools. The concept of 'branding' educational programs as Behavior Analytic is also explored and analyzed. Regulating the profession is a challenge, yet this is an important consideration for the field. This chapter will summarize what the empirical research tells us about applying behavioral principles to the treatment of ASD.