This study, the result of excavations stretching back to 1975, looks at the process of village formation during the second holocene era at Dhars Tichitt and Oualata in Mauritania, which make up the first large scale villagisation in the Sahara region. It seeks to answer such questions as why the villages were built, why they were sited where they were, and what the influences were on the architectural styles used. French text.