Multi-tiered systems of support (MTSS) are effective in addressing challenges in schools through a tiered system of support and diagnostics. A broad field of research has developed over the past 50 years. This systematic literature review aims to provide an overview of MTSS quality, outcomes, and characteristics in elementary education research. The review includes international studies and focuses on MTSS approaches that integrate behavior modification. After searching several databases, 40 studies published between 2004 and 2020 met the criteria for closer examination. The review presents study characteristics and theoretical references of different MTSS, including location, time, sample, study design, outcome measures, groups involved, interventions, and effects. In summary, MTSS have been found to be effective in elementary schools internationally, particularly for behavior change. Future studies should investigate the interactions between interventions within the school setting and involve teachers, school staff, and stakeholders in MTSS development to improve the system's coherence and effectiveness. It's important to note that MTSS have a political dimension that affects implementation and sustainability and can impact society by improving school experiences and reducing negative behaviors.