Amidst a context of ongoing educational reforms, Wales is striving to support strong pathways and smooth transitions for upper secondary learners. This report was commissioned to support Wales' ambitions for implementing the Curriculum for Wales and developing a cohesive, learner-centered upper secondary education system. The report explores how, internationally, countries organise upper secondary education, including the design of curricula and qualifications, and how these shape learner pathways and transitions. Drawing on insights from eight comparison systems and OECD-wide data, the report highlights policy pointers for Wales to support progression in learners' pathways and to enable transitions to further and higher education - and the world beyond - for all learners.