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The formation of the complex linear duties in the central Taklimakan Sand Sea is discussed based on analyses of wind regimes, sand grain size distributions oil the topography of the duties, and a combination of geomorphic and geophysical investigations into the morphology of the dunes. Complex linear dune formation is shown to have five stages. Analysis clearly shows that under the control of wind regime, sand supply and other factors, the simple linear duties move sideways while they evolve. This is the main cause for the formation of complex linear dunes in the central Taklimakan Sand Sea. We have not collected enough evidence to show whether the complexity of the complex linear dunes is left over from previous wind regimes or whether the previous wind regimes had different dominant wind directions compared to those of modern winds. The evolutionary processes of complex linear dunes in the region partly support the theory of ’barchan evolution’ but do not support the ’roll-vortex’ and ’bimodal wind regime’ hypotheses. After the complex linear duties were developed, the local wind regime and the other controls such as sand supply suggest it is possible for them to maintain their linear shape. The evolutionary process discussed is limited to the region indicated in this paper, and may not be applicable to the whole Taklimakan Sand Sea. There are different evolutionary processes in different dunefields because of variations in the factors that control complex linear dune formation. Copyright (C) 2004 John Wiley Sons, Ltd.