The purpose of this qualitative study was to explore and describe the extent to which registered nurses’ practice was affected by emergency department overcrowding. Participants were recruited from a tertiary hospital by using the purpose sampling method. Data collection was done using a semi-structured interview guide. Individual interviews were conducted with eight registered nurses working in the paediatric emergency department. Data analysis was conducted using thematic content analysis and Yin’s (2003:178) five-phase cycle. The study findings revealed that the lack of professional nurse leadership and the difficult existing relationship with the physicians were obstacles that had to be obviated if the paediatric ED were to function optimally and best practice were to be achieved. It was revealed that a problematic issue in the setting was that the most critical decisions on allocating where patients should be treated were made by physicians who have more authority than nurses. It was recommended that the ED need to be clearly defined in the policies as an outpatient, emergency care or as an episodic patient care area as “Admission” can mean admission to the ED or admission as an inpatient/boarded patient. / Health Studies / M.A. (Health Studies)