This thesis presents a comprehensive characterisation of the Palaeolithic occupation of the Thar Desert, which is located in western India and south-western Pakistan. This is achieved through a combination of extensive syntheses of existing palaeoenvironmental and archaeological evidence and the development of new, interdisciplinary evidence for Upper Pleistocene hominin occupation in the Thar Desert through surface survey and excavation. Patterns of environmental variability in the Thar Desert are described to identify when and where the Thar Desert may have been habitable to hominin populations. Evidence for over 900 Palaeolithic sites is synthesised to identify existing spatial, typological and chronological patterns in the Thar Desert. Typo-technological descriptions of new Palaeolithic assemblages are described, and placed within chronological and environmental contexts based upon associations with previously studied sediment formations. The results of chronological, environmental and archaeological analyses from a new excavated site, Katoati, are described, which presents a significant new benchmark for Palaeolithic studies, both for the Thar Desert and southern Asia. The excavated assemblages from Katoati indicate a Middle Palaeolithic occupation of the Thar Desert during episodes of enhanced humidity >91ka, and a further Middle Palaeolithic occupation 65-55ka. These Middle Palaeolithic assemblages indicate considerable cultural continuity and offer a chronometric framework for the results of the surface survey. The identification of a number of technologically and typologically distinct artefacts in both excavated and surface contexts indicate significant similarities with Middle Stone Age assemblages from Arabia and the Sahara and Middle Palaeolithic sites in South Asia. As a result, the Thar Desert can be identified as a pivotal location for investigating major changes in Upper Pleistocene hominin demography between Africa and across southern Asia.