['Despite the potential benefits of total quality management (TQM), many healthcare organisations encountered difficulties in its implementation. The purpose of this paper is to explore the barriers to successful implementation of TQM in healthcare organisations of Iran.', 'This study involved a mixed research design. In-depth interviews were conducted with TQM practitioners to explore TQM implementation obstacles in Iranian healthcare organisations. In addition, this study involved survey-based research on the obstacles associated with successful TQM transformation.', "TQM implementation and its impact depend on the ability of managers to adopt and adapt its values and concepts in professional healthcare organisations. Unsuccessful TQM efforts in Iranian healthcare organisations can be attributed to the non-holistic approach adopted in its implementation, inadequate knowledge of managers' about TQM implementation, frequent top management turnover, poor planning, vague and short-termed improvement goals, lack of consistent managers' and employees' commitment to and involvement in TQM implementation, lack of a corporate quality culture, lack of team orientation, lack of continuous education and training and lack of customer focus. Human resource problems, cultural and strategic problems were the most important obstacles to TQM successful implementation, respectively."] Does why TQM work in Iranian healthcare organisations?