Objectives <p>Improving quality of life (QoL) is a priority concern for persons with intellectual disability and integral to the principles and practices of applied behavior analysis (ABA). Study objectives were to evaluate QoL perceptions among participants who were behavioral service providers using quantitative-qualitative (mixed methods) research methodology.</p> Methods <p>Participants (<i>n</i> = 139) completed an online survey questionnaire that inquired about definitions of QoL and how QoL can be assessed through observation, input from care providers, and self-report.</p> Results <p>Survey findings found that participants defined QoL according to several common categories extracted from open-ended survey responses and consistent with many QoL indicators represented in the literature. They also endorsed several approaches to QoL assessment derived from scale-based ratings.</p> Conclusions <p>Behavioral service providers acknowledge the importance of QoL for persons with intellectual disability but could benefit from training focused on QoL, implementing QoL supports with service-recipients, and adopting a QoL framework informed by more expansive applied research.</p>