As a response to the challenge posed by an increasing number of agitated and violent patients, there is in Canada a growing number of psychiatric intensive care units (PICUs), in both general and psychiatric hospital settings. In this article, the functioning of such a unit in a general hospital context is reviewed. Statistically significant changes in average length of stay (LOS) were observed, with an increase from 5.8 to 7.3 days over the period studied. The factors influencing the functioning and LOS of this PICU are analyzed. A possible "deskilling" of the staff in other wards is discussed, and alternative explanations are hypothesized in an attempt to shed light on the interaction between this unit and its environment.