Federal law allows for paraprofessionals to provide instruction to students with developmental disabilities if they are adequately trained and supervised, but how to best provide this training and support remains unclear. In this paper, we update a systematic review of experimental studies that test the efficacy of paraprofessional-implemented interventions for students with developmental disabilities. We identified 36 studies published 2012-2019. An exciting development is that some researchers are shifting to testing teacher-implemented training, therefore beginning to address important questions about the feasibility of widespread implementation under real-world conditions. Based on findings across studies, recommendations for practice include that (a) paraprofessional roles be well-defined and focused on the implementation of evidence-based practices; (b) paraprofessional training should feature modeling, an implementation checklist, and performance feedback that is sustained over time; and (c) administrators should ensure that teachers have the time and support that are required for effective paraprofessional training and supervision.