The peculiarity of the French educational system, regarding the ICT, is to be provided by an exclusive competencies referential. This deliberate choice aims at a learning continuity and progression and it is directed at the reduction of the digital break. The choice is interpreted by a recognition system of the achieved competencies from primary school (the B2i® : ICT Patent) until the university (the C2i® : ICT Certificate). But these ministerial prescriptions are not evident and are collided, in a recurrent way, in relation to the problem of the teachers formation. Thus, the ICT Certificate for teachers - C2i2e - was created. It counts on the national referential whose objective is to identify the specific professional competencies in the exercise of the teacher's duties and profession in a new educational context.Therefore, our research concerns the problematic of the C2i2e introduction within the Universities of Teachers Education and, in a particular way it concerns the problematic of the competencies evaluation related to the referential of C2i2e. The experimentation with the educators professional practices showed the difficulties that they have, not only to delimit these competencies but also to evaluate them.From that moment, it seemmed to us essential to date back to the origins of this referential's conception in order to better understand which the issues related to this professional certification are. Our objective is to observe the special way that the designers conceive this evaluation tool and the way it can reveal itself unsuitable for those who use it. The research question with which we work is about understanding how a conceptual tool such as this competencies referential could be operational in the professional practices of the educators.We propose to consider the human activity as a unity of observation, especially by the device set up for the C2i2e by mobilizing the activity theory (Vygotski, Leontiev and Engeström) and, Rabardel's resumption, The concept of instrument given by Rabardel also allows us to consider the referential as a problematical artefact and that at the same time is viewed as an instrumental relation in which it is assimilated like a semiotic object made by the designers for a certain use within a collective of educators and to reach the teaching trainees, as well.On the other hand, to adapt the concept of "common world" mentionned by Béguin, for the analysis of the C2i2e activity, allows to attribute the difficulties found in the characteristics of the situations rather than the characteristiques of men. This original transposition is supported by an underlying theoretical framework that is the concern of the current of the psychologic-historical-cultural, represented particularly by Vygotski, Bruner and Meyerson.Through an ethnographic survey, we carried out a qualitative study based on semi-directed interviews with the educators who were confronted by themselves at the C2i2e in the framework of their formation device. Then, we matched their representations with those of the designers in order to answer our hypothesis in which the conception activity related to the use of the referential C2i2e is a process during which the designers and the educators must adapt the heterogenous "worlds" that are met, understood and answered.The results of this research take us to manifeste the need to conceive collaboratively a true evaluation tool for the C2i2e. To conceive is not only to make a prescriptif artefact, but also to define especially its characteristics. From the close point of view, the evaluative activity analysis of the authentication devices of the C2i2e could give us an additional lighting on the design of the competences evaluation.Béguin, P. (2003). Design as a mutual learning process between users and designers Interacting with Computers, Volume 15, Issue 5, October 2003, Pages 709-730 Béguin, P. in Pastre, P. & Rabardel, P. (2005). Modèles du sujet pour la conception. Dialectiques activités développement, Ed. Octarès. Toulouse. Engeström, Y. (1987). Learning by expanding : an Activity-theorical approach to developpemental research. Helsinki : Orienta-Konsultit Oy. Leontiev, A. N. (1981). Problems of the development of the mind. Moscow : Progress Publishers Meyerson, I. (1949). Les fonctions psychologiques et les œuvres. Paris, Vrin. Vygotski, L. (1978). Tool and symbol. Cambridge : Harvard University Press. Rabardel, P. (1995). Les hommes et les technologies. Approche cognitive des instruments contemporains. Paris : A. Colin Rabardel, P. (2001). Instrument mediated activity (p. 17-30). In A. Blandford, J. Vanderdonckt and Ph. Gray (Eds.) Situations, People and Computers XV-Interactions Without Frontiers. Springer-Verlag.