The fact that most Chardonnay wines have common olfactory properties which allow wine experts to recognize them is now well established (Ballester et al., 2005 and 2008). The authors studied a set of 29 Chardonnay and 19 other white monovarietal wines, all from 1999-2000 vintages and unoaked. Participants (members of the Chardonnay du Monde ® wine competition) were asked to evaluate the Chardonnay wines exemplarity level. Orthonasal and overall assessments were performed, providing two exemplarity scores per wine. Results showed an exemplarity gradient from bad to good and a significant correlation between the two assessment conditions. Two groups of wines with contrasted levels of exemplarity (bad vs. good examples) were selected then analyzed by Gas Chromatography-Olfactometry coupled to Mass Spectrometry (GC-O-MS). Seventy two volatile compounds were identified. This specific Chardonnay olfactory space has been tentatively linked to the relative concentrations of 29 volatile compounds, regarded as aroma-impact compounds. The relative concentrations (Ai/Ais) of the 29 volatile compounds were found to contribute positively or negatively to the exemplarity level of the Chardonnay wines. These findings suggest that these 29 compounds play a predominant role in Chardonnay olfactory characteristics, although this remains at the level of a hypothesis (Ballester, 2004). The other compounds could constitute the chemical environment in which the 29 compounds were expressed together. . More recently, additional investigations were conducted on new selection of wines, all from 2003-2005 vintages and unoaked, using the same sensory (exemplarity scale) and physico-chemical approaches (GC-MS-SIM) as Ballester (2004). . The sensory approach sought to determine: i) the level of consensus between wine professionals in the assessment of wines, to confirm the hypothesis that experts have a collective image of the odor quality of Chardonnay wines; ii) the distribution of the exemplarity scores, to confirm the hypothesis that Chardonnay wines are organized along a gradient of exemplarity from which two groups with different exemplarity levels (bad vs. good example) could be formed; and iii) the constitution of these two groups (the proportion of Chardonnay wines in the group of good examples and inversely for Non-Chardonnay wines), to confirm the existence of a specific Chardonnay olfactory space. The physico-chemical analysis sought to determine: i) which volatile compounds present in the new set of wines could account for the wine exemplarity scores; and ii) whether these volatile compounds were similar to those previously identified. The patterns of sensory results were similar to those reported by Ballester et al. (2005). From chemical point of view, the relative concentrations of 35 volatile compounds were shown to play a role in the wines’ exemplarity scores, on mean-comparison tests confirmed by Partial Least Squares analysis (PLS). Eighteen of the 35 compounds were also among those found by Ballester (2004). These compounds seem to be vintage-independent and as such might represent the core of the Chardonnay wine olfactory space. The other 17 seem to be specific to the new wines tested and might contribute to the fuzziness of the boundaries of the Chardonnay wine olfactory space. These results emphasize the complexity of the odor quality of Chardonnay wines, with some volatile compounds stable across vintages, while others are vintage-specific.