  This paper focuses on the study of a practical management problem faced by a
healthcare {\it emergency department} (ED) located in the north of Italy. The
objective of our study was to propose organisational changes in the selected
ED, which admits approximately 7000 patients per month, aiming at improving key
performance indicators related to patient satisfaction, such as the waiting
time. Our study is based on a design thinking process that adopts a {\it
discrete event simulation} (DES) model as the main tool for proposing changes.
We used the DES model to propose and evaluate the impact of different improving
scenarios. The model is based on historical data, on the observation of the
current ED situation, and information obtained from the ED staff. The results
obtained by the DES model have been compared with those related to the existing
ED setting, and then validated by the ED managers. Based on the results we
obtained, one of the tested scenarios was selected by the ED for
implementation.
