Engagement and performance in mathematics at the upper secondary level have been the concern of successive governments in England. This report was commissioned as part of the country's policy reflections for transforming how maths is viewed and experienced in England. The report explores outcomes such as the share of students studying maths and performance across countries, and how education systems internationally deliver mathematics in upper secondary. It also examines factors shaping maths education, including the expectations set by curricula, student pathways, cultural perceptions, and the needs of the labour market and higher education.