This chapter explores radical personal change and its relationship to well-being, welfare, or prudential value. Many theorists of welfare are committed to what is here called the future-based reasons view (FBR), which holds (1) that the best prudential choice in a situation is determined by which possible future has the greatest net welfare value for the subject and (2) what determines facts about future welfare are facts about the subject and the world at that future time. Although some cases of (...) radical change are intuitively prudentially good, many cases of really radical change are not. Yet FBR has trouble explaining this. Many people instinctively reach for the notion of identity to solve this problem—arguing that really radical change cannot be good because it alters who someone is. Yet, as the chapter argues, there are reasons to doubt that appeals to identity are appropriate. The chapter ends with the suggestion that prudential facts may explain why and when retaining identity matters, rather than the other way around, and points to a possible way forward for a theorist of welfare committed to FBR. (shrink)