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The paper begins by examining the importance of southern African Quaternary environmental change. The Quaternary is characterised by repeated climatic changes of considerable amplitude; analysis of these fluctuations reveals the ubiquity of change and the fundamental dynamism of earth systems. Change is normal and, despite the fact that southern Africa was not subject to Quaternary glaciation per se, the influence of variations in, say, amount and seasonality of rainfall, has been very marked indeed. The Quaternary also represents the time period during which people have become a dominant environmental agent in the subcontinent; southern Africa has played a crucial role in the evolution of hominids and their development has been influenced strongly by accompanying environmental change. The relationship between geomorphology and climate in southern Africa is explored, revealing the degree and extent to which its landscapes are determined by changing environmental conditions, especially during the Tertiary and Quaternary; how apparent is the legacy of the past? This leads to a consideration of the types of geomorphological evidence, some more reliable than others, that can be utilised in order to reveal the details of Quaternary environmental change. Arid and semiarid landscapes appear to preserve more evidence of former environmental conditions, although high contemporary erosion rates and the paucity of long terrestrial-sedimentary sequences hinder their complete elucidation. Two case studies of Quaternary change in the subcontinent are presented, from the southwestern Cape and Namibia. These examples document the increasing intensity of human impact on landscapes to the extent that people now play the dominant geomorphological role, especially in semiarid and coastal areas. The conclusion offers pointers as to how geomorphological evidence of Quaternary change can be used to assist in the better management of contemporary and future environmental conditions. (C) 2001 Elsevier Science B.V. All rights reserved.