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Many recent studies propose a simultaneous assessment of employment growth and productivity. They make it possible to better understand the adaptation of territories to changing economic constraints and opportunities. Within the framework of the geographic economics, average territories should experience positive or negative cumulative phenomena. However, some empirical studies reveal intermediate situations. This is the case for the ?le-de-France area, which belongs to the group of territories characterized by a model of growth described as recessive. This paper shows that this conclusion largely depends on the method applied and on the data used. We proceed in three stages. The first recalls the terms and stakes of the debates that structure the literature devoted to the evaluation of the respective roles of the territory. The second reconsiders the case of the ?le-de-France region in order to discriminate between these two effects. Thanks to the application of the Shift-Share method, we conclude that the geographic effect is negative at the regional level only. Referring to a finer territorial scale enables us to go further in the justification of the simultaneous observation of high performance and of negative local effects. We show that the logic of polarization that leads to agglomeration effects differs according to the area under study.