Members of People Unlimited Inc, maintain that they are proof that physical immortality is possible, despite the death of their founder. In this dissertation, I address the paradox of immortalist lifeworlds: how can members of People Unlimited maintain that they are immortal, yet also claim that members are still susceptible to death? This dissertation is about how imagined futures make up the present for radical life extension (RLE) activists, who form part of an emergent immortalist biosocial landscape where anticipation acts as a way of recognizing the future as a model for the present. Understanding how immortalists can claim to be physically immortal in the present, yet always working toward immortality, requires consideration of the cultures and communities within the broader RLE movement, human relationships to finitude, relationships between science and religion, and biomedical imaginaries. Since little ethnographic data exists on these communities, the goal of my research is to provide a general overview of the contemporary social phenomena of immortality, with an ethnographic focus on People Unlimited and Alcor Life Extension, both in Scottsdale, Arizona, and the broader RLE community that attends the yearly Revolution Against Aging and Death Festival (RAADfest) in Las Vegas, Nevada. The dissertation argues that RLE is an emergent form of biosocial citizenship among healthy individuals, whose present biological limitations are overcome by an orientation towards the future. / Dissertation / Doctor of Philosophy (PhD) / Members of People Unlimited Inc, maintain that they are proof that physical immortality is possible, despite the death of their founder. In this dissertation, I address the paradox of immortalist lifeworlds: how can members of People Unlimited maintain that they are immortal, yet also claim that members are still susceptible to death? I argue that for many immortalists, anticipation acts as a way of recognizing the future as a model for the present. I explore how radical life extension activists, including immortalists, transhumanist, cryonicists, and others, create immortal futures through self-care regimens in the present. I connect their future and present by examining the promissory and hopeful discourses of modern bioeconomies, and the forms of affect used in the creation of immortal biosocial worlds.