This article presents the application of the systemic problem structuring approach Viable System Diagnosis (VSD) within the Department of Orthopedic Surgery in a large hospital in Norway. It explains why systemic thinking is relevant to this uniquely complex form of human organization. The department was coping with systemic dysfunction and VSD was chosen because previous applications demonstrated VSD excels at diagnosis of what is causing dysfunction. VSD was employed through a participatory framework that included in the process, among other stakeholders, medics, technologists, managers, administrators and, as far as possible given the sensitive nature of patient information, the patient. VSD guided thinking about what the organization is set up to do and the existing organizational arrangements to achieve that. The outcome was an agenda for debate that guided stakeholder discussions toward ways and means of improving organizational arrangements. The article briefly reviews previous applications of VSD in the hospital sector and other large complex organisations.