Sacred space has conventionally been identified with architectural typologies tiedto specific ritual functions or with the iconography and disposition of sacred images within a building.1 Recent research suggests a more dynamic model in which sacred space is defined by the interaction of the viewer/worshipper with architectural space, sacred substances including relics, as well as holy images within the context of communal rituals and private devotions.2 It has also been argued that sacred space is activated through the appeal to all of the senses by a wide range of stimuli, including the smell of incense, the sight of natural and artificial lighting, the sound of chant or the spoken voice, the touching and sometimes kissing of material images, the taste of a ritual meal and the choreography of movement within space.3 Such an interpretative model seems particularly apt for the basilica of San Marco in the aftermath of the Fourth Crusade. Although Venice’s rulers had already acquired Byzantine relics and images prior to the thirteenth century, they now began to refashion their own sacred space in the palace chapel in unprecedented ways. Within the pre-existing architectural framework (Figure 29.1), a five-domed Greek cross structure derived from the Apostoleion in Constantinople, an appeal was made both to individual worshippers and pilgrims and the collective audience of the state rituals on major feast-days, adapting certain aspects of Byzantine sacrality to a distinctly western preoccupation with vision and ostension around the turn of the thirteenth century.