The edition of Nietzsche's correspondence is concluded with the commentary on the letters from and to Nietzsche in the crisis-ridden period from 1887 to 1889. The effort required for the commentary is particularly great for this time, as nearly every document from the period has been subjected to intense comment and interpretation. Renate Müller-Buck, who has proved her worth in editing the letters from the very beginnning of the project, has not only been involved in collating and accessing the manuscript resources (particularly the drafts of letters) but has over and above this devoted her attention to unravelling difficult personal connections, personal and literary allusions and the complicated networks in this wide-ranging correspondence. The comprehensive index to Section III, to which Holger Schmid has made an equal contribution, now provides access to the final and most complex episode in Friedrich Nietzsche's life and work.