Synthesizing the breadth of current research on the teaching and learning of writing, the third edition of this definitive handbook has more than 90% new content, reflecting the growth and dynamism of the field. Leading scholars--including many international voices--review major theories, developmental issues, and instructional approaches for students at all grade levels. Cognitive and sociocultural aspects of writing are explored in depth, as are assessment principles and methods. Issues in teaching students with disabilities, multilingual students, and culturally diverse students are addressed. The volume discusses innovative research methods and educational technologies and identifies key directions for future investigation. New to This Edition *Chapters on executive functions in writing; disciplinary writing in math, science, and social studies; the role of vocabulary in writing; and formative assessment. *Chapters on source-based writing, source evaluation, and writing development and instruction for African American students. *Chapters on sociocultural aspects of writing--from critical literacies to agency and identity, social justice issues, and more--plus an emphasis on integrating cognitive and sociocultural perspectives throughout.