Parker and Carlisle (Journal of Advanced Nursing 24, 771-778) argue that there is a scarcity of empirical research focusing on issues such as supernumerary status and mentorship in Project 2000 courses from the students' perspective. This paper presents the findings of a longitudinal cohort study using Grounded Theory to discover the effect(s) of mentorship on student nurses following the introduction of the 1992 programme of education leading to a Diploma of Higher Education in Nursing and registration with the United Kingdom Central Council (UKCC). The cohort consisted of 10 students from a large Scottish College of Nursing & Midwifery who were interviewed on five occasions during the three years of their course. Students also kept a diary to record their thoughts and experiences regarding mentorship during their practice placements. In addition, a further seven students volunteered to participate by diary only. Data were analysed with the aid of NUD.IST and subjected to the constant comparative method of analysis. Findings indicate that Diploma students quickly lose their idealistic view of their mentor and over time develop an insight into the qualities they perceive are required of an effective mentor. Students quickly become aware of the importance of choosing good role models and learning their own mentor's likes and dislikes as they realize this impinges on the outcome of their assessment. As students move into their Branch programme, a gradual distancing from their mentor is evident. This coincides with a development in their confidence, skills and a holistic perspective of care.