Despite his considerable influence on the development of ESP and all our professional lives, almost nothing has been written about John Swales' distinctive prose style. Based on a 340,000 word corpus comprising 14 single-authored papers and most chapters from his three main books, this paper sets out to identify the main features of this style. Using frequency, keyword and concordance analyses, I compare the Swales' corpus with a broader applied linguistics corpus of 710,000 words and identify self mention, hedging and attitude, reader engagement and considerateness as characteristic of Swalesian rhetoric. I conclude with the view that this is a disciplinary voice informed by a keen assessment of his readers and representing an independent creativity shaped by an accountability to shared practices.