The subject of this dissertation is the introduction and reception of science fiction literature in Sweden 1950–1968. Apart from considerations on science fiction as a genre and market category, and a brief survey of science fiction published in Sweden before the year 1950, the dissertation scrutinizes the Swedish publishers’ attempts at introducing both domestic and translated science fiction, the reception of the genre in Swedish literary criticism, the magazines Häpna! (1954–1966) and Galaxy (1958–1960), and the foundation of a Swedish science fiction fan culture. Science fiction was established as a category on the Swedish book market in the early 1950s, with several attempts to launch single works or whole series of mainly translated fiction. Between 1952 and 1968, roughly 30 publishing firms published over 160 books marketed as science fiction, with an apex in the late 1950s. Few publishers were successful, however, and most of the series were discontinued within just a few years of their inception. Meanwhile, in Swedish literary criticism, science fiction was increasingly perceived as a deficient form of commercial entertainment. A few of the exceptions were Harry Martinson (1904–1978), with his space epic Aniara (1956), and the translated author Ray Bradbury (b. 1920), who came to be considered as surpassing the boundaries of the genre. With the magazine Häpna!, a Swedish science fiction fan culture was contrived, with fans forming clubs, arranging conventions, disseminating fanzines, and, eventually, starting their own publishing firms and magazines. In the Swedish literary system, science fiction became a semi-separate literary circuit of production, distribution and consumption, and, concurrently, a growing autonomous subfield of cultural production, with its own forms of specific symbolic capital, doxa, and instances of consecration.