This handbook summarizes contemporary research on practices to train staff delivering applied behavior analysis (ABA)-based services for autistic individuals. Despite the rich literature documenting the effectiveness of these practices, intervention programs may encounter numerous challenges, such as staff turnover and burnout, which can impact the training program and negatively affect the quality of services. Supervisors play an important role in establishing the conditions to prevent and address staff burnout and turnover but often lack the skills and experience to do so effectively. Unfortunately, survey research suggests that supervisors may not be trained to develop these skills. This chapter describes some common challenges related to training (i.e., staff burnout, turnover, feedback receptivity) and summarizes variables that may cause or mitigate these challenges. In addition, this chapter proposes topics to prioritize when training supervisors and summarizes potential barriers and solutions.