Dr. HARRISON Mark G.Mendoza, Norman B.Norman B.MendozaKing, Ronnel B.Ronnel B.KingHocson, Sheila Marie G.Sheila Marie G.Hocson2026-03-022026-03-022026School Psychology International, 2026.0143-03431461-7374http://hdl.handle.net/20.500.11861/26852<jats:p>School counsellors with a strong professional identity have a stronger sense of purpose, better role clarity, and greater job satisfaction. However, the factors that shape professional identity, particularly the role played by school leaders, remain underexplored. In this sequential explanatory mixed-methods study, we investigated the relationship between supportive leadership practices and the professional identity of school counsellors. Using Self-Determination Theory as the theoretical framework, we surveyed 168 counsellors and interviewed 13 counsellors in the Philippines. Quantitative results revealed that autonomy-supportive leadership was significantly associated with a stronger professional identity. Qualitative findings showed the potential underlying mechanisms: counsellors with autonomy-supportive principals felt understood, had a voice in decision-making, and felt empowered to take on leadership roles. Competence support showed no significant impact, while relatedness support had mixed associations with professional identity. This study is novel in applying Self-Determination Theory as a framework to understand the role of leadership practices in school counsellors’ professional identity. The findings hold implications for leadership practices that promote professional growth among counsellors and the effectiveness of school counselling.</jats:p>enBasic Psychological NeedsSchool CounsellingProfessional IdentityPhilippinesGlobal SouthPeer Reviewed Journal Article10.1177/01430343261421926