The long felt absence of a trustworthy critical edition of Philostratus’ Life of Apollonius of Tyana has been remedied by the publication of the new Teubner edition of this text, published in 2022. In the preface to the edition the publication of a companion volume was announced. This book fulfils this promise. After an introduction dealing with the transmission of the text and with Philostratus’ Greek there follows an extensive series of critical notes in which a large number of editorial choices are explained. In these notes much attention is paid both to the morphological and syntactic peculiarities of Greek of the Imperial period in general and to the idiosyncratic syntax employed by Philostratus in particular. The notes deal with every aspect of the text, ranging from the use of particles and word order to moods and tenses, and containing ample discussions of conjectures and interpretations of earlier scholars. This book is an indispensable working tool for scholars using the new Teubner edition of the Life of Apollonius. It also caters for the needs of students of Greek language and literature in general, and especially of those interested in the Second Sophistic and the works of Flavius Philostratus.