The objective of this research was to explore the "on-the spot" clinical interventions mental health nurses make in critical incidents on inpatient psychiatric wards. Mental health nurses play a key role in the management of psychiatric critical incidents. Nurses' autonomy, decision-making, and training in clinical interventions are important issues in psychiatric nursing practice. A descriptive study was conducted among mental health nurses working on inpatient wards of three major psychiatric hospitals in the greater Athens area, using semi-structured interviews. Nurses' personal views also were documented. Semi-structured interviews were conducted with 103 mental health nurses, who were encouraged to make personal remarks. The results of this study show that in the majority of critical incidents, the nurses were found to be in contact with the psychiatrist on call; physical restraints were used frequently in violent episodes; reassurance and support were common interventions; the majority of nurses would have preferred not to intervene with critical incidents; and nurses expressed a need for skills training and higher autonomy. The nurses implemented a specific number of interventions in confronting the various types of crises. The need for specialized training was noticed and problems like accountability, autonomy, and medication administration, were considered crucial by the mental heath nurses.