Brown, who has a knowledge of at least 26 languages, has been instrumental in the development of the study of late antiquity as a field. Within this broad field, he has also been central in the study of Augustine, monasticism (both the eremitical "holy man" and coenobitic alternatives), the cult of the saints and the practice of sexual renunciation. More recently, he has made fundamental contributions to the study of power relations in late Roman society and to the study of financial giving. He has produced a steady stream of articles (several being classics in the field) since 1961, and a steady series of influential books since 1967.