Different lines of archaeological research have been developed in order to increase our knowledge of the history of the hunter-gatherer societies that inhabited the western Pampas of central Argentina, South America, during the Late Holocene. Recently, stable isotope data from human remains have been included. This paper presents the first group of δ13C and δ15N results obtained for this region. On this basis we identify spatial and chronological patterns that may have interesting implications at the levels of spatial organisation and temporal changes. Then, we evaluate the existence of correlations with other lines of archaeological evidence. Finally, we propose an agenda for future work including the generation of a robust regional isotopic ecology that will provide the context for the development of specific dietary reconstructions. Copyright © 2009 John Wiley & Sons, Ltd.