During the past three decades there have been far-reaching changes in how the book of Isaiah is understood and interpreted by scholars. From widespread acceptance of the view that it was the legacy of three different prophets working at different periods in Israel's history, new perceptions have focused on the fact that, although not the work of one single author, it has been composed as a single book. Its message is focused on four central themes: (1) the LORD God of Israel is the only God; (2) the divine promise to the royal house of David assures Israel of protection among the nations; (3) Jerusalem is destined to become a place of light and truth for all peoples; (4) Israel's exile among the nations is both judgement and redemption. This study discusses a fuller engagement with the work of many scholars who have carried Isaiah studies into a fruitful new period of understanding. It brings to light a richer understanding of the nature of biblical prophecy which had, for too long, been frustrated and rendered sterile by over-hasty assumptions regarding authorship. As a result a new period of interpretation has revealed a fresh theological understanding of the message of this great book - undoubtedly the greatest of all the biblical prophets - that is of direct relevance for both Jews and Christians. This is volume 416 of Journal for the Study of the Old Testament Supplement series.