ABSTRACT The introductory essay to this special issue on Nineteenth-Century Interstitial Spaces begins by noting the period’s pertinence for scholars exploring interstitiality, which as a concept may have existed in earlier historical eras but, as Tim Ingold, Roger Luckhurst, and others have argued, can be more forcefully aligned with the post-Enlightenment values of modernity. We tease out connections within and between the eight contributions to the issue, exploring the relationship between nineteenth-century spaces and other possible (spiritual) worlds, interstitial elements in the Victorian rural, colonial, and urban landscape, and, finally, interstitiality and interior spaces such as the Victorian office. Our own contribution then applies the idea of interstitiality to Eleanor Catton’s neo-Victorian novel The Luminaries (2013), pinpointing its attunement to the nineteenth-century experience of interstitial spaces and its allusion to particular Victorian practices and stories. Building on existing research influenced by the so-called spatial turn, the eight essays gathered here represent another, more recent scholarly shift highlighting the material properties of technological artefacts against their phenomenological or ideological impact.