Most teams in hospital medicine are ad hoc, meaning that the teams vary in participants. Ad hoc teams can be found in academic teaching hospitals where team members change across shifts and rotations. Due to varying team membership, these teams face significant hurdles, because they lack an opportunity to develop a team identity, shared mental models, and trust. This article discusses facilitators and barriers to effective functioning of ad hoc teams. Communication, conflict management, power, and leadership are areas that either serve as facilitators or barriers to positive team function. In addition to discussing these aspects, solutions and recommendations from practice are shared. Solutions include data about successful teams, communication in those teams, and data about how to improve education and team training. These practical applications can be applied in practice to improve team functioning. Finally, we recommend that additional research be conducted in the area of ad hoc teams, because this type of team is a large part of medicine with a gap in evidence.