Relative to peers without disabilities, students with disabilities are more likely to experience exclusionary discipline. Specifically, students with disabilities experience disproportionate levels of restraint, seclusion, out-of-school suspension, expulsion, and contacts with law enforcement. Further, after controlling for race (Black/African American) and gender identity (male)--demographic characteristics known to predict higher rates of exclusionary discipline--scholars have documented that the effects of disability persist. To reduce exclusionary discipline and improve student outcomes, many (>25,000) schools in the U.S. implement a continuum of social, emotional, and behavioral (SEB) support within a positive behavioral interventions and supports (PBIS) framework. This evaluation brief explores the relationship between (a) schools' implementation of Tier 1 (universal) support within a PBIS framework; and (b) the proportion of students with disabilities suspended.