Book excerpt: This book provides teachers with an entirely new approach to developing and using classroom-based language assessments. This approach is based on current theory and practice in the field of language assessment and on an understanding of the assessment needs of classroom teachers. The following key questions are addressed: • Why do I need to assess? What beneficial consequences do I want to help bring about? How can my assessments help my students learn better and help me improve my teaching? • When and how often do I need to assess? What decisions do I need to make to help bring about these beneficial consequences? • What do I need to assess? How can I define the abilities that I want to assess? • How can I assess my students? What kinds of assessment tasks should I create? How can I score my students’ responses to these tasks? The authors guide the reader step-by-step through the process of developing and using classroom-based assessments with clear explanations and definitions of key terms, illustrative examples, and activities for applying the approach in practice. Extra resources are available on the website: www.oup.com/elt/teacher/lact Lyle Bachman is Professor Emeritus of Applied Linguistics at the University of California, Los Angeles. He serves as a consultant in language testing research projects and in developing language assessments for universities and government agencies around the world, and he conducts courses and training workshops in language assessment. Barbara Damböck was Director of Studies of the English Department at the Teacher Training Academy in Dillingen, Germany, from 2003 to 2011. From 2003 to 2017 she supervised the training of oral examiners for the certification examination for elementary school English teachers in Bavaria. She has extensive experience as a classroom teacher, teacher trainer, and teacher of teacher trainers. She conducts courses and workshops for teachers and teacher trainers around the world.