Tiered systems of support in education

This paper examines Multi-Tiered Systems of Supports (MTSS) and related tiered frameworks in compulsory education across OECD countries. It synthesises academic research and policy documentation on MTSS, as well as closely related approaches such as Response to Intervention (RTI) and Positive Behavioral Interventions and Supports (PBIS), to clarify their conceptual foundations, core components, and intended contribution to inclusive and preventive education systems. The paper reviews available evidence on academic, behavioural, and attendance-related outcomes, and analyses how tiered frameworks are designed, governed, and implemented in different education contexts. Particular attention is given to system-level features that shape implementation, including leadership and coordination, data use and assessment infrastructure, professional capacity, and alignment with broader inclusive education policies. The paper concludes by outlining key considerations for education systems seeking to implement or strengthen tiered support frameworks.