A summary of inclusion and co-teaching syntheses was conducted to better understand the evidence base associated with collaborative models of instruction. Six syntheses were identified: four investigated inclusion, and two investigated co-teaching. Collectively, the syntheses represented 146 studies. The syntheses investigated research on collaborative models; student outcomes; teachers' attitudes, beliefs, and perceptions; and students' perceptions. Common themes of collaborative models were identified across the six syntheses, which included collaborative models; student outcomes; teacher support issues; and attitudes, beliefs, and perceptions of collaborative models. Findings provide an empirical foundation to assist school psychologists in evidence-based decision making. (Contains 3 tables.)