There is a burgeoning interest in how best to support and facilitate the development of writing and writing output of research students. One pedagogy is the use of writing groups for and beyond the period of the doctorate; however, there is relatively little empirical research that helps explain "how" the pedagogies of research writing groups actually work. This article draws on academic literacy, and writing research and practices to explore what is learned, and how learning occurs through participation in research writing groups. This pedagogical analysis is developed by reference to a retrospective evaluative study of research writing groups in one large metropolitan university. Through self-reporting by members, and as demonstrated in practice, scholarly writing was learned in complex and timely ways; one particular feature was through the construction, articulation and critique of peers' texts. (Contains 1 table.)