"Liberty is a revised and expanded edition of a modern classic of liberalism, Four Essays On Liberty, regarded by Isaiah Berlin as his most important book, and constantly discussed since its publication in 1969. Irving Howe described it in Harper's as 'an exhilarating performance - this, one tells oneself, is what the life of the mind can be'." Berlin's editor Henry Hardy has told the story of the book's genesis, revised the text, identified sources, incorporated a fifth essay that Berlin had wanted to include, and added three further pieces, so that Berlin's principal statements on liberty are now gathered together. Three appendices drawn from Berlin's unpublished papers help us to understand the core of personal conviction from which his writings sprang. A guide by Ian Harris to the huge literature stimulated by Berlin's ideas completes the volume.