Background: Specialist nurse students are upon graduation certified to have increased their professional competence to an advanced level. But how do specialist nurse students themselves experience and understand their professional competence and its development upon graduation? This is what this study aims at describing. Method: This study has a phenomenographic approach. Data consists of student written narratives. Results: The participants understood their professional competence developed in various degrees as a transformation in me and a transition in my encounter with the patient. Being able to integrate theory in practice was crucial for this competence to develop. Conclusion: The specialist programme needs to support students in developing an alliance with the patient and promote patients' self-management, self-efficacy and promote students' possibility to integrate theoretical knowledge into practice. The result becomes an important input in the formulation of the assessment criteria for professional competence.