The present book aims at setting a new and complete critical edition of the Greek astrological work Anonymous Commentary on Ptolemys Tetrabiblos (= Anon. in Ptol.), written between the V and VI centuries A.D by an astrologer presumably educated at the Neoplatonic School of Alexandria.

Although there is a humanistic edition by H. Wolf (Basel, 1559) and two Latin translations of Anon. in Ptol., nevertheless the Greek text established by Wolf is highly defective, due to the fact that he relied on just one 'recentior' manuscript (the cod. München, Bayerische Staatsbibliothek, Gr. 59). That is the main reason why the Anonymous Commentary on Ptolemys Tetrabiblos need to be studied again, so that a modern critical edition will be made, provided by a complete critical apparatus of textual variants.

The critical edition is based on a thorough analysis of the textual tradition and on a complete collation of the twelve main manuscripts containing Anon. in Ptol. Aside of the critical text of this work, a Byzantine recensio of the anonymous commentary, written by Isaac Argyrus in Constantinople at about 1370, will be edited as well. Argyrus recensio is very useful for understanding many difficult passages of the late-ancient commentary.

To conclude, this edition seeks to fill an important gap in the studies on the textual tradition and reception of Ptolemys Tetrabiblos, the main Greek astrological handbook from his first appearance in II century A.D. until today.