Positive Behavior Interventions and Support (PBIS) is a framework for defining, teaching, encouraging, and maintaining appropriate positive behavior in students and staff. PBIS is a three-tiered research-based process. The first tier, Universal Supports, is effective for approximately 80% of students and focuses on school-wide procedures and common areas. Tier II, Selected Supports, in combination with Tier I, is effective for approximately an additional 15% of students for whom Tier I alone was not effective. Tier II focuses on small group and class-wide strategies.