Henry Hardy is a Fellow of Wolfson College, Oxford, Isaiah Berlin's principal editor, and one of his literary trustees. He began editing Berlin in the mid-1970s as a graduate student at Wolfson. Previously an editor at OUP, Hardy has been working full time on Berlin since 1990 and has now edited or co-edited 18 of his books, as well as a four-volume edition of his letters - the last volume of which (Affirming: Letters 1975-1997, co-edited with Mark Pottle) was published in September 2015 by Chatto. He is also the editor of The Book of Isaiah: Personal Impressions of Isaiah Berlin (Boydell, 2009).