With its multidisciplinary and applied foci, team-working skills are seen as especially critical in business courses in general and in business information systems courses in particular, and are specifically incorporated into desired graduate attributes by many universities. Past research has focused on the benefits of group working but little work has been conducted to examine the relative contribution of group formation choices on academic performance. This paper reports on a study that develops and validates a data-collection instrument and identifies four underlying factors that influence formation of groups: convenience, social cohesion, task management and technical skills/knowledge. The results thus suggest that academic performance is influenced by the skills and knowledge of individual members, potential social cohesion among the group members and the task management ability considered at the group formation stage. The study notes that while how a group is formed influences ultimate academic performance, how the group operates is also an important factor. (Contains 7 tables.)