Many fan scholars have argued for a literary approach to fanfiction as an ideal venue for illuminating reader-response theory. I extend this argument to consideration of texts for young people, as this genre is wedded to a construction of audience that is alienated from the means of production. I focus upon Harry Potter fanfiction; the popularity of both the books made fan practices more visible than ever before. I argue that great fanfiction is often unpublishable, since it draws its aesthetic power from both its freedom from the constraints of the publishing industry and its embeddedness within a community of readers and writers: fanfiction, unlike published literature for young people, relies upon a presumption of readers’ knowledge, rather than their ignorance.