In Contra sermonem Arrianorum, written in ca. 418, Augustine reflects, from the height of his trinitarian theological insights, on the series of theses (sermo) of an anonymous author of latin Arianism. The theology of this anonymous author is similar to the theology of a later opponent of Augustine, the Arian bishop Maximinus. The sermo is completely handed down at the beginning of Augustines reflections. \nThe present edition replaces the over 300 year old Maurine edition, is based on a larger number of manuscripts, and offers for the first time a critical apparatus which corresponds to modern standards.