Recruiting and retaining excellent teachers remains a pressing policy issue in education systems worldwide. According to UNESCO estimates, 68.8 million teachers will need to be recruited globally to meet Sustainable Development Goal 4. However, simply recruiting more teachers will not be enough to meet this challenge: we need to recruit high-quality teachers who provide high-quality lessons to improve learner outcomes – and who will remain in the teaching profession. The high number of teachers who leave teaching early in their careers means that there is a crisis in teacher retention, and high staff turnover constitutes a major drain on the resources available to develop a strong education system. As part of our commitment to research and development, we have invested in the review of our Future Teaching Scholars Assessment Centres. Our new Data Insights report examines the Assessment Centres' validity and reliability, and correlations between candidates’ performance in different aspects of the initial assessment and later classroom performance.