As a topic of concern to educational researchers, writing is enjoying something of a renaissance, particularly with respect to the transition between secondary and post-secondary levels of schooling. In the context of this renewed interest, this article presents a framework for understanding composition that integrates cognitive, textual and social dimensions. I explore how each of these three dimensions contributes to our understanding of the challenges that student writers face when composing. I also discuss ways in which the increasingly social focus of much research on composition offers new ways of thinking about the cognitive and textual dimensions. Finally, I propose that integrating these dimensions in our study and teaching of composition can help us to better understand and address the challenges that students face in moving across educational contexts.