Difficult assignments and long texts force writers to adopt strategic behaviours. This study looks at strategies employed by adult writers composing long texts, i.e. thinking as they write, processing, working over and elaborating knowledge in the act of writing, as opposed to merely reproducing it. In more academic terms we might say: engaging in epistemic and heuristic activity. The book presents ten different types of writer. The typology it proposes is based on the evaluation of statements by approx. 6,000 persons, both professionals and students.