Together, the chapters in this book provide an overview of the various ways in which formative assessment may be used to support teacher professional learning, and shed light on choices that can be made in designing such assessments. The studies illustrate how teachers may perceive formative assessment methods, how their learning processes might unfold during formative assessment processes, and which struggles they may have to deal with during the process. The book furthermore addresses questions concerning the impact of formative assessments on teacher learning. As such, this volume provides theoretical as well as practical prospects, as well as challenging ideas for how formative assessment may move further towards being an effective means for supporting teacher learning. This book was originally published as a special issue of .