Multi Tiered Systems of Support (MTSS) is the name for a number of systems of support for students including Response to Intervention (RTI), and Positive behavior interventions and supports (PBIS).  MTSS is a system in which a multi-tiered approach is used for the early identification and support of students identified at-risk or students who are performing below standards, either academically or social/behaviorally. 

The instructional approaches used within the general education setting should result in academic or social/behavioral progress for the majority of students. The primary focus of MTSS is early intervention to accelerate academic success and social-emotional well-being. Students in the MTSS process receive evidence-based intervention, in addition to core content instruction. Ongoing progress monitoring and frequent data collection guide all instructional decisions to improve learning outcomes and to increase student achievement.