The open-air site of Andance (Saint-Bauzile, Ardèche, France), located on the left bank of the Rhône river, is perched upon a basaltic dome (552 m) that has become isolated from the Coirons plateau by erosion. The site, jeopardised by the open-air mining of Miocene diatomite, was the object of a rescue excavation over some 3 500 m2 undertaken by Paléotime in 2008 and is comprised of a valley fill-sequence bearing a Middle Palaeolithic industry at its base, though in a secondary position among geliflucted megaforms with basalt blocks. Stratigraphic, use-wear and petro-archaeological approaches underline the considerable impact of postdepositional processes on the artefacts and highlight their significant redistribution. The technological study confirms the assemblage was reworked as well as sorted, but not contaminated by more recent industries. All the raw materials used at Andance were imported to the plateau as it is completely devoid of flint sources. These raw materials comprised quartz and quartzites collected from one or more drainage systems in proximity to the site, but mostly Barremo-Bedoulian flint selected from reworked formations associated with the Oligocene conglomerate which covers the limestone formations of the Barrès plateau, roughly 5 km from the site. They bear witness to regular access to a local mineral source. However, the local basalt was not exploited, which is in contrast to the documented behaviour of Neanderthals from the same period in the Massif Central. The main chaîne opératoire, represented from start to finish, focuses on the production of non-Levallois blanks, seldom retouched. The principal products obtained are éclats débordants (continually, partially, or cortically backed) as well as different flake forms normally associated with a discoid production method. One or several other chaînes opératoires are attested by the presence of Levallois products displaying diverse techno-morphological criteria and by a significant percentage of elongated products. Part of this production was carried out elsewhere and imported to the site. Tools (n = 62) compose 4.6 % of the total pieces with the Mousterian group being largely dominant with a scraper index of 94. Retouching, often located on the thickest edge of the piece, is generally scaled, short, or semiabrupt tending towards marginal and only slightly modifies the morphology of the blank. On the other hand, bifacial shaping and pebble tool reduction sequences are essentially carried out in quartzite; these are probably incomplete and spatially fragmented. Quartz and quartzites, whose use is always limited on other sites of the region, play a distinct and determinant role: quartz represents a backup material whose exploitation is almost identical to that of flint, yet less diversified, probably due to its structural and textural properties. Quartzites are employed as part of a ‘complementarity economy’ (Huet, 2006) where they occupy a particular function and may be used in specific activities. The combined importation of shaped pieces and pebbles reinforces the distinct economic and functional status of this material. The assemblage is assigned to a Mousterian techno-complex rare in bifaces and with a discoidal knapping method, which lies at the transition between early and late Middle Palaeolithic, probably earlier than OIS 5. The analysis of the pedosentimentary microfacies suggests that the basalt blocks and the industry were deposited before isotope stage 5. A thermoluminescence date obtained on a burnt flint has provided a terminus ante quem for the occupation of around 93 ka. This natural promontory offered numerous advantages and certainly played a decisive role in the choice of occupation for the Mousterians of Andance (i.e. protection and observation). We cannot precisely reconstruct the everyday landscape of the Neanderthals who camped here; we may however presume the existence of a basaltic grit of blocks in the course of being exposed on the highest points and an occasionally humid small valley at the foot of the site. The geographic configuration was clearly paramount in the choice of location and it was around this base that seasonal activities were organized. The strategy of lithic provisioning adopted by the Mousterians of Andance seems to support this and corresponds to a ‘provisioning of places’ as defined by Kuhn (1995). Rare exotic pieces such as silcretes demonstrate longer displacements outside of the normal economic territory. The different approaches and analyses developed for this site allow us to further our regional understanding of Neanderthal behaviour and shed new light on research perspectives for open-air sites. The geographic proximity and similar chronology to the site of Payre (dir. Moncel, 2008) offers potential for comparison, especially concerning questions of raw material economy and the spatial exploitation of a particular territory.