Education is not only a learning process but also a psychological process so teachers take on the role of educator-mentor. In addition to good teachers, they must be good mentors and good animators. Thus, it is very important for teachers to be involved in training activities that will lead them to professional development and will help them meet their role requirements more effectively. The purpose of this work is to describe the process of designing, implementing and evaluating an educational seminar for secondary school teachers on issues related to the role of the teacher in preventing the use of psychoactive substances. The results of the seminar evaluation show that teachers have educational needs in relation to the subject matter and their training is considered very important. Designing and implementing a seminar that responds to the needs and expectations of teachers for their role in substance prevention can have positive effects on individual teacher goals and actions in relation to the subject.