The use of applied behavior analysis (ABA) to treat persons with autism goes back several decades. Many specific target behaviors and intervention strategies have been developed. In the last two decades the most heavily studied of these methods has been Early Intensive Behavioral Interventions (EIBI). This package of ABA methods is unique in two ways. First, a broad range of target behaviors are trained for 20-40 h per week. This training is much more treatment per week than what is described in most ABA studies. Second, the children treated are typically 2-3 years of age, which is younger than for most ABA research. Reviews of EIBI have typically focused on the efficacy of the methods. These are important, but at present we argue that these methods are effective. This paper is different in that it looks at current trends such as generalization, parent training, factors that mitigate against effective treatment and the need for follow-up and booster treatment.