This article is focused on empirical studies on factors that may facilitate the effective learning and teaching of writing. Three domains of psychological oriented writing research are presented: writing processes, learning to write and writing to learn. First, some results from cognitive psychology focusing on writing processes (e.g. Bereiter Scardamalia, 1987; Hayes Flower, 1980), individual differences (e.g. Galbraith, 1996) and the relation between processes and text quality (e.g. Breetvelt, Van den Bergh, Rijlaarsdam, 1994) are reviewed. Results showed that writing is indeed a complex activity and that a large variation is represented in writing processes and in the effectiveness of these processes. Second, some studies in the field of referential communication about learning to write are presented (e.g. Couzijn, 1995; Holliway McCutchen, 2004). The major conclusion is that acting as a reader, and observing reading processes (e.g. of texts similar to the text the writer had to write or wrote) are very effective learning activities that contribute to writing skills. Next, attention is paid to the effective ingredients of observational learning in learning-to-write instructional sequences (e.g. Zimmerman Kitsantas, 2002), and to individual differences in observational learning (e.g. Braaksma, Rijlaarsdam, Van den Bergh, 2002). It is found that when students observe writers at work (models), it has larger learning effects than when they write texts themselves. Results also showed that depending on the proficiency of the writer and the newness of the task, reflecting on weak models and good models may have different learning effects. After that, attention is directed on (individual differences within) writing to learn: the paradigm in education that builds on the assumption that the act of writing can support learning (e.g. Klein, 1999). Finally, some issues where psychology could contribute to the teaching of writing are presented.