The excavation of the site of Cassagna 2 (Blagnac, Haute-Garonne), carried out by AFAN (French National Archaeological Association) from August to November 2001 (Tchérémissinoff et al., 2002), was due to the development of the « Aeroconstellation » ZAC (Commercial Business Area) on the outskirts of Toulouse. This excavation was surrounded by other occupation sites: to the east, by the Chalcolithic sites of Cassagna 1 (directed by Sébastien Lacombe) and to the west, by an Early Bronze Age site, Cassagna 3 (directed by Fabrice Pons). They had been preserved by the loamy cover of the land rising above the second bottom of the Garonne, approximately 3 km to the west of its present bed. The site was revealed thanks to the discovery of two sheets of artefacts trapped in vast palaeo-depressions. The sheet corresponding to Sector 1, preserved over 1400m2 (fig. 2), has been dated to the Late Bronze Age IIIb. To the north-west, the «Chalcolithic sheet» (sector 2), the object of this article, extends over approximately 340 m2. The discovery of the three « Cassagna » sites, covering the entire sequence of the Late Neolithic and Early Bronze Age, represents an extraordinary opportunity to gain clearer knowledge of these periods in the Toulouse region. The alluvial terraces of the Garonne do not provide the best fossilisation and prior information concerning this period was mainly provided by certain sites in the Aude region known as the Véraza group (Guilaine ed., 1980). Closer to home, some finds including closed units had revealed a clearer regional characterisation (Vaquer, 1990, p. 345). However, such new references to these «impersonal» facies from the boundary of the western extension of the Véraza group and its transition manifestations towards the Bronze Age were very welcome. In terms of the Bell Beaker phenomenon, the region had already provided a major excavation, the site of Lapeyrière, Muret (Jolibert, 1988), which revealed a fine series of ceramics composed of decorated elements which can be attributed to the Pyrenean facies (Guilaine, 1984) as well as numerous elements belonging to the Bell Beaker «common ware» type (Besse, 2003, p. 18). In this series, only 6 of the elements seem to belong to the regional Chalcolithic, which motivated its specifically Bell Beaker attribution. This is often the case in Western Languedoc where «exclusively» domestic occupations seemed to have predominated over «mixed» occupations (Guilaine et al., 2001, p. 254). The importance of the Chalcolithic basis for the formation of the Early Bronze Age is moreover frequently observed and this aspect undeniably constituted a supplementary difficulty in recognising Bell Beaker dwellings. Nevertheless, even on sites defined as «exclusively Bell Beaker», decorated ceramics are never in the majority: there is no reason therefore for them to be indispensable for this definition. And if the non-decorated «series» from the regional Chalcolithic and from specific types of common ware ceramics both marked the formation of the Early Bronze Age, they are also likely to have produced original variations: an authentic mix. This recognition obviously raises problems but will probably help identify the domestic manifestations of the Bell Beaker style. With this aim in mind, we consider that the site of Cassagna 2 constitutes a satisfactory example. The good state of conservation of the surface of sector 2 and the homogeneity of the ceramic series make it possible to suggest their attribution to a stage of regional evolution of the Bell Beaker productions. This would be accomplished without the help of the decorated ceramics, thanks to the presence of characteristics specific to the pottery known as «common ware» within a series not exhibiting, on the contrary, any exclusively Véraza elements. The presence of notched saws, considered as an indication of the Languedoc Chalcolithic, does not go against this proposition. When added to the absence of cordons with digital impressions, it is quite coherent, in this context which is obviously prior to the first expressions of the Early Bronze Age. Moreover, the nature of the surface also evokes a stable establishment for this site which we think has preserved the fleeting imprint of at least one light building of around 16 m2 (fig. 5).