In a pediatric teaching hospital, the authors examined 16 novice medical case presentations that were classified as instances of a hybrid apprenticeship genre. In contrast to strict school and workplace genres, an apprenticeship genre results from the sometimes competing activity systems of student education and patient care. The authors examined these novice case presentations for the amount and patterns of time devoted to student learning and expert teaching, the difficulties created for participants, the sometimes misunderstood implicit messages delivered by experts, and the opportunities to address educational objectives. This study offers professional communication researchers a model that combines quantitative and qualitative methodologies to assess the effects of competing activity systems in the development of communication expertise.