Examining action research publications in leading Information Systems (IS) journals as a particular genre of research communication, this paper develops the notion of style composition to understand how authors structure arguments for contribution. The paper defines style composition as the activity through which action researchers select, emphasize, and present elements of their research practices to establish premises, develop inferences, and present conclusions in publications. While each publication is unique and leverages the underlying research practices in different ways, the paper identifies distinct styles that authors use to compose their argument. Premise styles relate to the dual goals of action research through practical or theoretical positioning of the argument; inference styles combine insights from the problem-solving and the research cycles through inductive or deductive reasoning; and, conclusion styles focus on different types of contributions—from-the-trenches, field study, framework development, problem-solving method, and research method. Drawing on the considered publication sample, the paper analyses the styles adopted in select publications, shows authors have favored certain styles while leaving others underexplored, and reveals important strengths and weaknesses in composition of styles. Based on these insights, the paper discusses how to further develop action research practices and writing as an important approach to engaged scholarship within the IS discipline.