Abstract Acute Assessment Units (AAUs) have been developed to meet the demand for emergency care. Traditionally, AAUs have been an admission route to secondary care but the role is now evolving to assessment. AAUs are complex and have many interactions both in hospitals and the community. The effective functioning of an AAU requires excellent clinical leadership, appropriate facilities, timely access to diagnostics and input from the multi-disciplinary team. Increasingly, AAUs will have to develop services which are not dependent on using hospital beds. A variety of emergency medical presentations can, with the appropriate resources, be delivered in an out-patient setting. [download-attachments container="div" style="list" display_icon="1" display_count="1" display__size="0"]