A systematic review of U.S. Special education teacher qualification policy: an interpretive synthesis with selected non-U.S. Evidence

Despite federal efforts under IDEA 2004 and ESSA, the U.S. special education teacher (SET) workforce still faces shortages, uneven distribution and high turnover. This systematic literature review and comparative interpretive synthesis (N = 53) examines how qualification policy has shaped the workforce and uses selected non-U.S. studies to identify organizational conditions supporting inclusive practice. A synthesis of legal texts, policy analyses, administrative-data research and other empirical studies reveals a professionalization paradox: qualification-centered reform raised formal standards but did not reliably reduce staffing inequities, improve retention, or address working conditions linked to attrition. The shift from the highly qualified teacher framework to ESSA-era state discretion changed the governance mechanism without resolving the underlying infrastructure deficit. The selected non-U.S. studies, used for interpretive comparison rather than as institutionally equivalent comparators, highlight recurring ecological conditions: distributed leadership, structured collaboration, role clarity and context-specific professional support. The proposed Occupational Ecology Framework conceptualizes SET quality as jointly shaped by credentials, internal capacity, work demands and constraints and systemic support. SET expertise contributes to inclusive capacity only when embedded in shared school-level responsibility. Qualification policy is therefore necessary but insufficient without sustained systemic support.