As an intense and sometimes disturbing experience with a strong visual dimension, the dream is a phenomenon that artists have dealt with since antiquity. In modern times, when dreams were considered an essential part of sleeping and were conceived of as a medium for the entanglement of subjectivity and the world, the potential of artworks to render these relations led to new aesthetic strategies for depicting dreams and sleep between 1860 and 1945. This chapter examines the rich and wide-ranging visual representations of dreams with a focus on western art and cinema and scrutinises how the state and experience of dreaming and sleeping have been artistically explored, transformed, and changed over time, and how they have contributed to changing the perception of sleep and dreaming. With both a chronological and systematic approach, we aim to trace the hypothesis of a growing localisation of the dream in the interior, first in subjectivity, and then in the unconscious. Three different strategies for representing dreams and sleep can thus be identified, each marked by a specific compositional model and pictorial logic. (1) The first consists of showing the dream as something externalised, formally dissociated from the sleeper’s body, and coming either from physical urges, imagination, or personal concern. (2) The second corresponds to the subjectivization of dreams, which becomes a micro-narrative, partly dissociated from the dreamer but emanating from the sleeper’s mind. (3) The third strategy shows the dream as internalised while rendering it as a way to the unconscious in the psychoanalytical tradition. We will show how these three stages or models to represent dreams and sleep in the arts and cinema—dream externalisation, dream subjectivization, and dream interiorisation—reflect the discourse on dreams in the given period (1860-1945), but also how they shape the conception of dreams. In each of these cases, the relationship between the space of sleep (reality) and the space of dreams (imagination) is subject to a different formal and semantic treatment, either to maintain their coexistence, to make one disappear in favour of the other, or to blur the boundaries between them.