The purpose of this meta-analysis was to summarize single-case intervention research studies in which students with disabilities received function-based intervention (FBI) within inclusive school settings to address challenging behavior. A total of 27 studies were identified and systematically reviewed to determine the overall effect of FBI on challenging and appropriate behavior and whether study characteristics moderated intervention outcomes. In addition, we summarized the following: (a) characteristics of study participants and settings, (b) characteristics of FBI applied within the studies, and (c) quality of the studies. Overall, FBI led to improved behavior in a variety of inclusive school settings. Interventions delivered after a teacher-administered functional behavior assessment and within the context of a whole group instructional arrangement resulted in significant reductions in challenging behavior and improvements in appropriate behavior, respectively. Implications for practice, future directions for research, and limitations are described.