It is possible to identify a literary genre “apocalypse” along the lines proposed in Semeia 14 (1979), as an account of a revelation mediated by a heavenly being that discloses a transcendent reality, both spatial and temporal. Apocalypticism, the worldview characteristic of apocalypses, can also be found in works that are not formally apocalypses. It is characterized by the belief that human life is largely shaped by supernatural forces, and bounded by the expectation of a final judgment, including the judgment of the dead. This essay responds to various objections that have been raised against this way of viewing the genre. It concludes by considering the modern adaptation of apocalypticism by Dispensationalists and Fundamentalists, and noting continuities and discontinuities with the ancient genre.