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In South Africa, organized dune stabilization began in 1845 in the western Cape with the introduction of Australian Acacia species which were regarded as the most useful plants for this process. Initially, seed was sown directly onto the sand, but in 1875 this was modified by spreading city refuse over the bare sand to temporarily stabilize the sands before seeding with Port Jackson Wattle and a few other species. This proved uneconomical because of the need to construct a railway line, and in 1896 a French technique was introduced. A foredune was formed at the source of the drift sand by constructing barriers with wooden poles or Marram Grass. The area behind this was then thatched with brushwood or seeded with grass before introducing alien woody species. Later the area was simply covered with seed-bearing Acacia branches. In the late 1940s it was realized that the ability of alien species to oust indigenous species posed a threat to the natural vegetation. However, it was not until 1974 that their use was curtailed. The present policy is to only stabilize areas when absolutely necessary, using indigenous species. An artificial foredune is no longer constructed, but brushwood packing prior to seeding is still undertaken. Indigenous seedlings, grown in nurseries, are also planted under the brushwood and successful stabilization takes at least five years. Harmful effects which arise from the use of alien species are discussed and include the ability of species to produce impenetrable thickets and suppress the growth of indigenous vegetation, the increase in the periodicity of fires, the draining of soil water resources and loss of cultivated land. The problem associated with stabilizing large sand drifts is the net loss of sand from beaches. Dune stabilization is an important management tool in the coastal zone, but there is a need for greater awareness of the problems associated with both stabilization using alien species and with badly planned development.