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The thesis presents a multi-proxy study of lunette dunes and explores their significance as palaeo-archives, that is, their potential for recording past environmental change and for improving our understanding of the drivers of past change. In particular, the work presented in this thesis provides new insights on the palaeo-history and past water availability in the Murray-Darling Basin (MDB), Australia, with the aim of contributing to long term reconstruction of palaeo-environmental change in this critical agricultural region for Australia. The work pertains a multi-site investigation of lunette dunes within the MDB and consists of the use of different investigative strategies to examine how lunettes record/respond to change. These include a statistical analysis, used co-jointly with qualitative analysis of lunette sediments, designed to improve the characterization of lunettes facies and the palaeo-information inferable. The results of this component of the thesis allowed for the identification of major lunettes facies, which reflect specific processes in multiple locations. However, results also showed that these facies were characterized by a more complex sedimentary history than previously described. Such a history has resulted in intra-facies heterogeneity ascribable to the occurrence of different combination of processes occurring at a local (site specific) scale. This highlighted the importance of using records of multiple lunettes at different sites to reconstruct palaeo-environmental change and the value of using adjacent/connected geoarchives to explore the role that the geomorphic context plays on lunettes evolution. Based on this, a broader landscape analysis was undertaken. This included the development of chronology for lunettes themselves and the sedimentary and geochronological analysis of the lake basins adjacent to the lunettes, as well as adjacent fluvial deposits. This analysis demonstrated that the response of the MDB lunettes to palaeo-change