Paraprofessionals spend the most time with the neediest students, but receive the least amount of training and support. All target students in the study had developmental disabilities, were between the ages of three and five, and had a history of challenging behavior. Paraprofessionals in the study were recruited because they had the least experience and training administering behavior support plans (BSPs) in their setting. A multi-level consultation model was used to train paraprofessionals (i.e., teaching assistants) to implement individualized BSPs. First, paraprofessionals were trained in a one-on-one setting how to implement the BSPs using behavioral skills training. Next, adherence to the BSP was monitored by independent observers and additional support was delivered contingent on meeting an adherence criterion. Through a cascading logic, data showed that paraprofessionals engaged in immediately and significantly higher levels of BSP adherence following application of the multilevel consultation model, and as a result, students engaged in immediately and significantly lower rates of challenging behavior (Tau-U = -0.97 to -1), which maintained over time. Further, all adult participants rated the procedures as highly acceptable. Thus, with minimal training provided to each paraprofessional across the study (M = 151.2 minutes), and dramatic observed changes in challenging behavior, the multilevel consultation model proved highly efficient, effective, and acceptable. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]