This paper introduces a feature on the relationship between two topics from related research areas: the professional gestures of the teacher whose study was based on the research developed in the field of ergonomics and language activities whose analysis has its source in the field of linguistics and psycholinguistics.

After recalling the conditions of emergence of these two topics, we shall evoke some of the points of convergence that enabled the researchers to cross their approaches: the methodological constraints related to their subject of study and the common goal of defining the professionalism of the teachers have created some porosity between the approaches from these two families of research.

However, despite a similar focus and a common desire to understand how the language traces inform about what actually happens in the classroom, differences remain because the central concepts of action and activity continue to have different meanings depending on the context reference in which they are employed. But these differences help to advance knowledge