<![CDATA[Curriculum reform has become a strategic priority in global education, and in Indonesia this has been reinforced through the Deep Learning policy within the Merdeka Curriculum. Although the policy promotes meaningful, mindful, and joyful learning, recent empirical studies indicate that its implementation at the senior secondary level remains limited, particularly regarding teacher adaptation, instructional leadership, and professional learning support. This study examines how school principals lead the transition toward Deep Learning, how teachers adapt their instructional and assessment practices, and how professional learning communities support this process. A qualitative multi-case study was conducted in two public senior high schools in Makassar involving eight participants: school principals, vice-principals for curriculum affairs, and teachers representing exact (science) and non-exact (social sciences and humanities) subject clusters. Data were collected through semi-structured interviews, non-participant observations, and document analysis, and analyzed using within-case and cross-case analysis with triangulation. The findings reveal two complementary leadership approaches curriculum governance and instructional leadership both of which strengthened teacher adaptation and professional learning communities. The study proposes a cyclical model of Deep Learning transition, emphasizing the reciprocal relationship among leadership, teacher professional learning, classroom practice, and contextualized local wisdom in supporting sustainable curriculum implementation.]]>
