In nursing training institutes, teachers support students with whom they establish a pedagogical relationship, while guaranteeing compliance with internal rules, particularly concerning the banning of cell phones during teaching. This complex double mission includes, among other things, the forbidding of cell phones in the classroom. Objective: this study aims at understanding the involved relational mechanism through the following question: how do teachers combine the pedagogical relationship with the authority they are required to exercise? Methodology: a qualitative study carried out between 2015 and 2016 using semi-structured interviews with teachers and students at the nursing school. Results: teachers give importance to the quality of the relationship, but act differently in order to link authority and training missions. Students accept and recognize this authority as it is part of the internal rules. This legitimacy allows for a cooperative pedagogical relationship to be established. The internal rules contribute to building up the authority of the teaching team. Conclusion: this study opens perspectives for reflection on the notions of relationships, rules, legitimacy, and collaboration. Authority is a complex phenomenon that fits, along with the pedagogical relationship, into a frame providing stability and legitimacy. The internal rules would not standardize the behaviors, but would allow for the expression of individual freedom.