Le coaching professionnel regroupe un ensemble de pratiques qui ne disent, a priori, rien de la posture du praticien. L’intervention qu’il met en œuvre relève des métiers de l’évaluation, il est ainsi nommé évaluateur-coach. Le dispositif dépend ainsi soit d’une logique de contrôle en posture de conseiller, soit d’une logique d’accompagnement en posture d’accompagnateur professionnel. Le travail de problématisation vise à questionner le rapport entretenu par l’évaluateur-coach avec son lieu de pratique. Il s’inscrit dans un cadre théorique de mise en tension des concepts d’évaluation, d’accompagnement et de lieu. En ce sens, l’utilisation de la méthodologie quantitative, qualitative des représentations sociales permet de questionner la représentation du coach sur son métier et son lieu d’exercice ainsi que le rapport qu’il entretient avec le lieu. À partir d’un échantillon de cinquante coachs, les résultats mettent en évidence une majorité de praticiens dans le guidage et le développement personnel. De plus, il est caractérisé à partir du rapport que l’évaluateur-coach entretient avec le lieu, des critères signifiants de la logique d’évaluation préférentielle du praticien. Les résultats sont modélisés à partir d’un kaléidoscope de postures en situation : le pilote orienté solution, le facilitateur maïeuticien, le praticien en développement personnel et le coach clinicien. / Professional coaching is a set of practices that in principle do not really reveal the attitude of the practitioner. The intervention he implements is about business evaluation and that is why he is called mentor-assessor. Therefore, such a scheme depends either on the idea of controlling businesses as a counselor or guiding them as a professional guide. The work of problematization here is to question the relationship maintained by the mentor-assessor with his place of practice. It is part of a theoretical framework putting together evaluation concepts, support and place. In this sense, the use of quantitative and qualitative methods of social representations allows to question the representation of the mentor-assessor on his work and his place of practice as well as the relationship he has with the workplace. From a sample of fifty coaches, the results show a majority of practitioners in the position of guidance and personal development. The report also points out that the mentor-assessor has with the workplace, meaningful preferential assessment criteria of the practitioner. The results are modeled from a kaleidoscope attitude situation which are: the solution-oriented guide, the birth coach facilitator, the practitioner in personal development and the clinician coach.

(in English): This thesis introduces the issue of reliability and validity of the dynamic assessment methods. In the theoretical part, the author briefly presents specifics of the dynamic assessment and various ways of verifying reliability and validity in the context of dynamic assessment. The text then summarizes ways of verifying reliability and validity for specific methods of the dynamic assessment based on experience from mostly foreign studies. The empirical part of the thesis aims to examine the relationship between the outputs of the ACFS method and characteristics of the assessors and subsequently to propose an optimal approach to the examination of the dynamic assessment methods. The results showed that the assessor was a statistically significant factor to the magnitude of the change in all ACFS scales. However, a more detailed analysis showed that the difference between the assessors varied across subtests. The qualitative analysis did not signify any relevance of specific characteristics to the differences between the assessors.