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The present study identifies 18 vegetation groups associated with the distribution of Thymelaea hirsuta (an evergreen desert shrub) in six types of habitat (coastal ridge overlain by calcareous dunes, inland ridges, saline depressions, non-saline depressions, inland plateau with skeletal soils, and inland siliceous deposits) in the western Mediterranean region of Egypt. Five of these groups are dominated or codominated with T. hirsuta (2 on the ridges, 2 in the depressions and 1 in the inland plateau). The effective complexes of soil variables in the phytosociological behaviour of this plant are calcareous sedimentation and fertility on the ridges, salinity in the depressions, and siliceous sedimentation and salinity on the inland plateau. Although it tolerates wide environmental gradients, it does not perform best at their extremes.