Aulus Gellius, who lived in Rome in the mid-second century AD, wrote his Noctes Atticae in twenty books; of this most survives but lacks the beginning, end, and all of book 8 bar the chapter headings. The work is a collection of mainly short chapters dealing with a great variety of topics including philosophy, history, law, grammar, and literary criticism. Gellius began collecting the material while a student in Athens, and assembled it later in life with the specific purpose of entertaining and instructing his own children. The manuscripts of Gellius have not been examined since the middle of the nineteenth century. This edition (in two volumes) presents a complete re-examination of the codices, several of which are earlier than previous editors have thought. Full collations are provided for the numerous fragmentary citations in the text, in the hope that they will allow a more accurate treatment of these fragments. In books 9-20 the readings of the ninth-century manuscript F are presented, on the basis of which the editor attempts to offer a new criterion for deciding between variant readings.