For decades, researchers and practitioners have been searching for the answer to the question, which is still relevant today, of what makes a teacher "good", that is, effective and efficient. The solution is also to be found in the instructor's personality. In the course of our research, we aimed to examine the personality of railway instructors. In addition to the analysis of general personality traits with the Big Five model, our sub-goals included the study of the instructor's assertiveness, basic attitude towards people, influence technique and conflict management method. We conducted our own research using a questionnaire method and widely used tools at four different organizations. Analysis of variance was used to examine differences between groups. Based on the results, the instructors have the right foundations to create a positive atmosphere. They are characterized by openness, friendliness and an above-average level of assertiveness, and Machiavellianism is present only to a small extent. In conflict management, compromise, problem solving and avoidance are the most typical styles. Based on the results, we recommend further increasing the level of openness and assertiveness, and instead of seeking compromises, we recommend the use of complex problem solving more often.