How did enclosed spaces shape Byzantine sanctity? This volume argues that confinement was far more than a physical reality: it constituted a dynamic category through which sanctity was experienced, represented, and negotiated across Byzantine devotional and material worlds. Bringing together fourteen contributions, this volume explores a wide range of enclosed spaces – from caves, monastic cells, prisons, and stylite pillars to tombs, bridges, and rock-cut hermitages – through literary, visual, and archaeological approaches. After a chapter-length introduction, the volume unfolds in six thematic sections that reflect its conceptual breadth and methodological diversity. Drawing on sources from across the Byzantine period, including hagiography, hymnography, rhetoric, manuscript illumination, and material evidence, it offers the first comprehensive exploration of confinement as a unifying framework for understanding Byzantine sanctity and its diverse spatial expressions. Its interdisciplinary perspective opens new avenues for comparative and diachronic research within Byzantine studies and beyond.