Instructional Consultation Teams (IC Teams) are an early intervention service intended to support teachers in working with struggling students. This is a large-scale experimental trial investigating the effects of IC Teams on teacher efficacy, instructional practices, collaboration, and job satisfaction. Public elementary schools (N = 34) were matched based on their risk composite and then randomly assigned to treatment or control groups. A multilevel model tested the effects of IC Teams on the beliefs and practices of teachers (N = 1,440) across three years of implementation. Results indicated that IC Teams had a significant effect on teacher efficacy and collaboration compared to randomly assigned control schools. The remaining effects were nonsignificant.