a b s t r a c t The Aterian is a distinctive Middle Palaeolithic industry which is very widely spread across North Africa. Its dating and significance have been debated for nearly a century. Renewed interest in the Aterian has arisen because of a recent proposal that its development and spread may be linked to the dispersal of anatomically modern humans. The industry contains technological innovations such as thin bifacially flaked lithic points and pedunculates as well as evidence for personal ornaments and use of red ochre. Such markers as shell beads are believed to be indicative of symbolic behaviour. Dar es-Soltan I on the Atlantic coast of Morocco contains a thick sequence of Aterian deposits that were thought to represent the later stages of development of this industry. New Optically Stimulated Luminescence dates and geomorphological study indicate a much older sequence and so far the earliest yet recorded ages for the Aterian. They suggest an appearance in the Maghreb region during MIS (Marine Isotope Stage) 5