Background: The relationship between medical students and patients has special characteristics that require to be well understood to prepare both students and tutors. Aim: To learn about medical students' thoughts and experiences once they start working with patients, how do they solve difficulties or problems and their perceptions about professional roles and patient rights. Material and methods: Qualitative study based on semi-structured interviews applied to 30 volunteer third year medical students who were beginning their clinical practice. The answers to open questions were transcribed and then analized and grouped by topics and categories. Results: Helping others was the main motivation to go to medical school. Other reasons were scientific interest and social status. Students felt prepared to communicate with patients. However they felt anxious, stressful and fearful of not being competent or not being able to answer patients' questions. There were some differences between male and female students' feelings. Nevertheless students declared that they had rewarding experiences with patients. They all recognized that patients have the right to reject being treated by students. The answers also showed that the first clinical experiences led to significant changes in their views of the medical profession. Conclusions: Students are aware of their trainee condition, the benefits that they obtain being in contact with patients and of their limitations. Patients must voluntarily accept to be subject of the students' training program and informed consent procedures need to be developed.