Given the academic benefits of assessment-driven teaching, and the growing accountability context of educational systems around the world, there is a rapidly developing need to educate teachers in effectively using assessments to promote, monitor, and report on student learning. However, assessment has historically been a neglected area in teacher education programmes, and empirical research has consistently shown assessment as an area of challenge for many teachers. While there is an increased focus across teacher education and professional literature on enhancing the assessment capacity of educators, there remains little empirical research on innovative and data-based strategies to effectively achieve this goal. The purpose of this text is to consolidate existing research on assessment education and to provoke innovative and effective approaches to educating teachers and teachers-in-training about assessment. Given the dearth of relevant research, this text also considers the matter of retention and extension of initial assessment learning into teaching careers. Combined, the articles in this text provide a foundation for novel thinking about developing teachers' assessment capacity from pre-service to in-service contexts. This book was originally published as a special issue of Assessment in Education.