Aims: An important characteristic of group work is the ability of members to evaluate each other's performance. We sought to examine the strategies deployed by students to assess the individual performance and contributions of colleagues. The exercise sought to promote collaboration between members, whilst rewarding individual contributions. Methods: Students worked in small groups to develop posters on a chosen topic. Electronic literature databases were used to search for information, and students completed learning journals to reflect on group interactions. During the poster assessment, students were asked to respond to questions on their topic. Eighty per cent of the marks were awarded for the poster presentation and 20% for individual contributions. Groups discussed members' contributions and awarded marks according to specific criteria. Some groups recorded their discussions, and the transcripts were subsequently analysed to identify strategies employed by students for awarding contribution marks. Results: Of the 180 groups who completed the exercise, 65% awarded unequal marks to individual group members (ranging from 9 to 20 (out of 20; mean 18.9; SD 1.3)). Conclusion: This exercise provided students with practical experience of working in a team, engaging in negotiations with colleagues, and adapting their behaviours to cope with challenging group processes. (Contains 1 table and 1 figure.)