Promoting self-determination has become a best practice in special education. There remains, however, a paucity of causal evidence for interventions to promote self-determination. This article presents the results of a group-randomized, modified equivalent control group design study of the efficacy of the Self-Determined Learning Model of Instruction (SDLMI, Wehmeyer, Palmer, Agran, Mithaug, Martin, 2000) to promote self-determination.
