None of the dating methods of marine faunal remains allows unequivocal age assessments. However, by combining several approaches, such as amino-acid racemization rates measured on a statistically significant number of samples, Th/U disequilibria, and by taking into account environmental isotope data (18O), it has been possible to set a stratigraphy of raised marine deposits of Pleistocene age in southern Peru and to identify unambiguously the terrace formed during the highest sea level of the last interglacial (isotopic substage 5e). There is an abridged English version. -English summary