The usual view of Kerouac’s Spontaneous Prose is that it is a matter of writing fast without reflection, and the story of Kerouac drafting On the Road in April 1951 by typing/composing the whole novel onto a roll of paper in a three-week marathon presumably legitimizes this view. However, this chapter argues that we should understand Spontaneous Prose as a reinvention of textuality rather than simply a matter of writing fast and without reflection, which in turn allows us to understand Kerouac’s responsiveness to modern media (film and analogue recording in particular) to the paradigm of conventional print textuality, bringing into view his development of what might be termed “post-print textuality” in even his seemingly more conventionally written novels. Ultimately, this chapter shows that Kerouac’s experiments with textuality rewrote the standards by which “good literature” in the postwar era was measured.