This article outlines some cognitive process models of writing composition. Possible reasons why students' writing capabilities do not match their abilities in some other school subjects are explored. Research findings on the efficacy of process approaches to teaching writing are presented and potential shortcomings are discussed. Product-based and process approaches to teaching writing are compared, with discussion and analysis of examples of writing that resulted from the two different approaches. The article draws out principles for teaching and learning, concluding that an approach to teaching writing that focuses on students' learning rather than on text outcomes may help to improve students' attainment in writing composition.