This book offers an overview of research regarding L2 writing and L2 writing assessment with the secondary aim of making L2 writing a central topic within the field of Second Language Acquisition. This monographic volume collects and summarises the different research trends in L2 writing and explores key concepts in L2 writing assessment. It provides a compendium of the research carried out from the 1980s onwards into the assessment of writing in a foreign/second language classroom across different educational levels, outlining the major tenets of research in the field. The assessment of language learners has had a growing impact in English language teaching and applied linguistics in the last thirty years. This field is in great need of work on the assessment of writing abilities in a foreign or second language and their implications for language teaching practitioners wishing to improve their students writing. This book addresses this issue from a theoretical, empirical and pedagogical perspective.