The purpose of this ethnographic study was to understand how nurses construct their practice in an acute inpatient psychiatric unit in light of the current challenges, demands and influences brought about by service reform. During a 5-month period, fieldwork observations, interviews and discussion groups occurred in a 22-bed acute inpatient mental health facility in New South Wales, Australia. The findings demonstrate how the current role of acute care has resulted in nurses working in increasingly complex environments characterized by competing priorities and new demands. Nurses struggled to fit the changed service philosophy with traditional models of practice within this fluid and changing environment. The findings are relevant within the context of current debates and can be used to enhance the understanding of contemporary acute mental health nursing practice and inform the continued development of mental health nursing in these settings.