[Truncated abstract] This ethnoecological study examines land uses by modern Martu Aboriginal people on their country. They occupy very remote settlements—Parnngurr, Punmu and Kunawarritji—in the Great and Little Sandy Deserts. In 1990, their country included Crown Lands and Rudall River National Park. The study investigated the proposition that the knowledge and practices of Martu were of direct relevance to ecosystem processes and national park management. This research commenced in the wider Australian research context of the late 1980s – early 90s when prevailing questions were about the role of customary harvest within contemporary Aboriginal society (Altman 1987; Devitt 1988) and the sustainability of species-specific harvests by Australian indigenous people (Bomford & Caughley 1996). Separately, there was a national line of enquiry into Aboriginal roles in natural resource and protected area management (Williams & Hunn 1986; Birckhead et al. 1992). The field work underpinning this study was done in 1986–1988 and quantitative data collected in 1990 whilst the researcher lived on Martu settlements. Ethnographic information was gathered from informal discussions, semi-structured interviews and participant observation on trips undertaken by Martu. A variety of parameters was recorded for each trip in 1990. On trips accompanied by the researcher, details on the plant and animal species collected were quantified. Martu knowledge and observations of Martu behaviour are interpreted in terms of the variety of land uses conducted and transport strategies including vehicle use; the significance of different species collected; socio-economic features of bush food collection; spatio-temporal patterns of foraging; and, the 'management' of species and lands by Martu. The research found that in 1990, hunting and gathering were major activities within the suite of land uses practiced by Martu. At least 40% of trips from the settlements were principally to hunt. More than 43 animal species and 37 plant food species were reported to be collected during the study; additionally, species were gathered for firewood, medicines and timber artefacts. Customary harvesting persisted because of the need for sustenance, particularly when there were low store supplies, as well as other reasons. The weight of bush meats hunted at least equalled and, occasionally, was three times greater than the weights of store meats available to Parnngurr residents. ... Paradoxically, hunting was a subject of significant difference despite it being the principal activity driving Martu expertise and practice. There is potential for comanagement in the National Park but it remains contingent on many factors between both Martu and DEC as well as external to them. The dissertation suggests practical strategies to enhance co-management.