The article analyses 'approaches', coming from various fields of study that are concerned with the teacher's knowledge base, with a view to making a contribution to the notion of "activity"; what it can offer to those interested in understanding the scope of the work carried out by teachers and how this understanding can help them to improve their work. The aim is to elaborate, in this fashion, a theoretical basis for exploring the range of 'understandings' possessed by the teacher, but with no pretension of exhausting the universe of existing questions, but rather, taking the investigation forwards, indicating the appropriate path for unpackaging the problems encountered. Firstly, the approaches found in the research on teachers' knowledge, are presented; secondly, the objective is to highlight an aspect that may be implicit, yet recurrent, in parts of this research. Lastly, contributions are made from ergonomics, of a Francophone base using an approach for the work that is 'ergo'-logical (anotherwords, the answer is implicit in the question) providing a perspective that emphasizes the importance of tackling the work from the notion of 'activity'. Such an approach - we wager - when based on a foundation of work that takes 'activity' as its focus, will increase inovative forms of knowledge production and lead to inovative ways of carrying out research into education, research that will make teachers the focal point, focusing on their work and their knowledge base.
Activity; Understandings; Values; Teacher's Work