Scotland, in common with many countries internationally, has been learning how to align ideas from research with policy and practice. This article considers what Scotland learned from large-scale evaluations of its Assessment is for Learning (AifL) programme and the extent to which this evidence was used to inform future learning within the national programme. More recently, the policy focus in Scotland has shifted to the creation of a new curriculum, Curriculum for Excellence, subsuming AifL. Merging curriculum and assessment innovations brought new challenges in the alignment of curriculum, pedagogy and assessment. Drawing on a Scottish Government-funded research project, Assessment at Transition, designed to identify and explore emerging gaps between practice in schools and local authorities and national curriculum and assessment policy aspirations, the article argues that assessment is learning and explores how formative approaches to evaluation at a national level might be used to prevent countries repeating past mistakes.