The ability of students to plagiarise coursework assessments has been a topic of much debate in recent years. The consequences of plagiarism for students may be devastating, since their failure to learn and use appropriate study skills will affect both their university experience and their subsequent career. This project set out to investigate students' perceptions of what constitutes plagiarism. A scenario-based questionnaire was given to undergraduate bioscience students from Level 0, that is, Foundation level, to Level 3. Analysis of the completed questionnaires showed student uncertainty about several aspects of plagiarism, including downloading of material from the Internet. Students were unclear about the distinctions between collusion, plagiarism and permissible group work. Thus, despite the media attention given to plagiarism, students are not always aware of the boundaries between plagiarism and acceptable practice. Since the penalties for plagiarising may be severe, it is essential that guidelines are provided early in the programme. A case-study approach is more likely to engage the students than issuing them with a set of penalties should they be caught. As a result of these findings guidelines have been produced, aimed at addressing misconceptions. Future work is planned to adapt the exercise to an interactive format within a managed learning environment. (Contains 10 figures and 1 table.)