This clinical exploratory research relates to the situation of a professional graduate nurse who, as part of a continuous training framework, benefits from an informal training period of a few weeks in a hemodialysis center. Analysis of the semi-directive interviews carried out with dialysis patients, nurse trainers, and trainee nurses enabled us to highlight the characteristics of the actors in this situation of on-the-job training, the general aspects of this training, the aim and stakes of the training, as well as the facilitating and blocking factors. Taking into account these elements allowed us to provide certain recommendations on training schemes, and to define the role of the framework of health in the implementation of this program. It also made it possible to question the relational training taking place within this training situation, which mixes three “othernesses”: the learner and his/her tutor, the dialysis patient whose body is being affected by the learning, and showing that the relational competence developed in the care process enriches relational competences in andragogy and vice versa.