The purpose of this study was to describe clinicians' perceptions of interprofessional collaboration in the intensive care unit and identify factors associated with interprofessional collaboration. We performed 64 semi-structured interviews in seven hospitals with ICU nurses, physicians, respiratory therapists, nurse managers, clinical pharmacists, and dieticians. ICU clinicians perceived two distinct types of facilitators to interprofessional collaboration in critical care: cultural and structural. In the critical care setting, cultural and structural facilitators worked independently as well as in concert to create effective interprofessional collaboration. Initiatives aimed at creating and facilitating interprofessional collaboration should focus attention on cultural and structural facilitators to improve patient care and team effectiveness.