What is meant by "learning in the workplace"? What is learned? How and with whom? These questions, far from constituting a new issue, are nevertheless highly relevant in the context of major and critical socio-economic changes affecting work, employment and training. The term “tutoring” is placed at the forefront as a lever used frequently by various socio-professional actors. What are the practices we can observe behind this terminology used in social discourse? The contributions gathered in this double issue explore how the interactions between actors, whether they are “field” tutors, “school” tutors, referents, professional masters, apprentices, alternates, trainees, etc., constitute a privileged way to study learning processes in the workplace. More specifically, we explore how the study of the conditions and modalities of the meeting between these actors allows us to reconsider the way we look at mentoring practices in the workplace. This interest for the actors, their encounters, but also their activity in its social, relational and interactive components unfolds over varied fields of study. These make it possible to document professional and training practices based on qualitative data from ethnographic approaches and research interventions.