Intensive care units encounter with the complex and different therapeutic and care needs of patients. The effective responsiveness to these needs depends on the knowledge and skills of different health professions, so inter-professional collaboration and teamwork is essential to providing safe and comprehensive care in these areas. Inter-professional collaboration is a process in which different health professions, along with the patient and their families work together in the interaction based on partnership, mutual trust and understanding, information sharing, common goals setting and joint decision making to achieve the best and most effective outcome for the patient. Unfortunately, most current performance in the intensive care units is parallel, independent and without the participation and joint decisions of different professions, and this is one of the reasons for the increase the medical errors and negative patients’ outcome. Numerous factors, including systemic, organizational, and interpersonal interactions, are influential on inter-professional collaboration in the mentioned wards, and understanding them will provide an opportunity to promote inter-professional collaborations in these areas. Strategies such as inter-professional rounds, the development of inter-professional common goals setting sheets, the preparation of guidelines, as well as the tools for measuring team performance and monitoring them can be effective in promoting inter-professional collaboration in intensive care units. It is time to adopt approaches and strategies to improve teamwork and inter-professional collaboration in intensive care units and improve patients’ outcome.