The authors explored two assumptions about college teaching and learning: first, that faculty teach in isolation, as institutional culture values and rewards autonomy over collaboration; and second, that faculty collaboration improves instruction. They present findings from an experiment in team teaching in a university beginning Spanish course in which they conducted action research to investigate the impact of team teaching on them, as the faculty participants in this study, and on their students. Data from students' course evaluations and the instructors' teaching diaries show that while participants expressed positive outcomes from team teaching, their concerns about professional identity, relationship, and engagement with students outweighed advantages.