The present volume is the ‘successor’ to The Cambridge Companion to Plotinus (1996). Over the last twenty-five years, there has been an enormous increase in published work on Plotinus and on late ancient Platonism generally. In addition, many scholars who had not even begun their careers twenty-five years ago are now working intensely in this area. This fact is reflected in the list of authors of this volume, none of whom appeared in the previous work and most of whom had not yet even begun their careers when the original Companion appeared.1