This paper aims to understand the processes which underpin teaching and which could justify professional attitudes, commitments and practices. The main goal is to contribute to the elaboration of methodologies for identifying knowledge used by teachers, and specifically that which is constructed through their lived experiences. In this paper, teaching is viewed as a set of professional activities, and not as an art or personal talent; thus the study focuses more on teachers than on teaching. Vocational studies tend to understand professional knowledge as a synthesis between knowledge which results from education and that which follows lived experiences. This synthesis results from the resolution by the actors of the contradictions between what standards and instructions imply, what theoretical knowledge indicates, and what professional reality shows. Such knowledge concerns not only current actions but also the work process itself: it is work process knowledge (Fisher, & Boreham, 2004). The resolution of contradictions and the elaboration of process knowledge depends on two kinds of factors: 1/ the actors, through their personal history, their individual goals and the competencies which they bring to collective activities; 2/ the organisation of the work situation, throughout resources allowing collaboration between professionals from different sectors, sharing of information and elaboration of new knowledge (Fuller, Hodkinson, Hodkinson, & Unwin, 2005).

These conclusions are tested within the French educational context through two case studies. Two teachers are observed during a 20 minute sequence and interviewed about this videotaped lesson. From the observation and the audiotaped comments by the teachers we can elaborate the repertoire of process knowledge used by them in order to accomplish their activities. The comparison between the two teachers enables some learning factors to be identified. Teachers’ learning results from: 1/ the reflective practices of these actors about their own professional activities; 2/ the actions and dialogues they conduct regularly with colleagues and other professionals. Those interactions seem to be fostered by the involvement of these teachers in specific transprofessional workshops aimed at stimulating the reflection of actors engaged in collective educational projects. These results confirm and refine our findings from a quantitative analysis on a wider scale (Grangeat & Gray, 2007).

These conclusions demonstrate the centrality of individual and collective actions and reflections to teachers’ professional development. They do not diminish the role of theoretical knowledge which is required in order to avoid the use of outmoded methods. Rather, they confirm the complexity of teaching and learning about teaching. Thus, it seems that continuing professional development programs should follow four principles: understanding teacher activities as widely unpredictable, as are all human actions; linking experiences, task awareness and knowledge in order to enhance teachers’ agency; supporting lifelong professional development processes; blurring the boundaries between professional and personal learning (Stevenson, 2000). Further studies are necessary to explore these conclusions.