This book works through the notion of the alien in contemporary philosophy. The authors attempt to think through politics, posthumanism, and alienation beyond and across the circuitry of thought that would otherwise enfold the alien in its regressive and parochial trappings. The figure of the Other has held critical thought in its sway for decades, to the point that we now suffer from a surfeit of alterity. This book considers whether the figure of the alien can offer us something better. It traces the outlines, intersections, and problems of emergent vectors of thought that coalesce around a renewed relationship to alienation: left accelerationism, xenofeminism, and inhumanism. Their common thread is the embrace of alienation as a positive force, transforming our progressive exile from a series of edenic harmonies - be they economic, sociological, or biological - into an esoteric genealogy of freedom. Appeals to alien forces can mask all too familiar prejudices, repackaging old assumptions in the language of sublime strangeness or harsh reality. This book seeks to move beyond this by looking at how the notion of the alien interacts with present problems and politics. It was originally published as a special issue of Angelaki.