The range and amount of writing taking place across all domains of life in the twenty-first century is expanding rapidly. At home, in school, at work and in the community, children, young people and adults write for numerous purposes and in multiple modes. Professional writers too capitalise on the multimodal diversity available and employ a range of materials and technologies. What it means to be a ‘writer’ in different domains and the myriad of influences upon individual writers’ texts composed in different contexts is part of the focus of this book. Predominantly it explores the identities of teachers, trainee teachers and students as writers, both within and beyond school. However, this chapter focuses on the identities of professional writers. It draws upon a cross-university study which investigated the nature of twelve UK-based professional writers’ identities and histories as writers and their composing practices.