APN in the United States encompasses a variety of collaborative models of care. Collaborative relationships with other disciplines such as medicine, pharmacy, social service, and physical, respiratory, and occupational therapy are an important component of the APN role. The collaborative relationship of the APN and physician is a unique one for providing optimal patient and family care. As changes in healthcare in acute care settings continue to occur, additional collaborative models for APN and physician care will only continue to help in meeting the healthcare needs of patients.