The commentary on Cicero’s De inventione by Grillius, the rhetor of late antiquity, was newly edited in 2002 by Rainer Jakobi. As a supplement, Jakobi now offers an introduction into and an in-depth annotation of the text. Jakobi first dates Grillius’ commentary to the turn of the fifth century and describes the academic culture of Grillius’ time, including his social context as well as his position in the long tradition of commentary on Cicero’s De inventione. In addition to a detailed discussion on the manuscript tradition and the reception of the text, the principal part of the book offers an annotation of the Grillius text lemma by lemma, always with a view to the original text, Cicero’s De inventione. Each section is preceded by an analysis, a representation of the structure and a commentary on the sources.