Since the introduction of the Emergency Services Enhancement Program (ESEP) in Victoria in 1995, improvements have been demonstrated in the indicators relating to Emergency waiting times, ambulance bypass rates and inpatient bed access block. This study focuses on staff perceptions of changes in these indicators, factors perceived to influence performance improvements and the extent to which ESEP is perceived to have contributed to overall patient care. A questionnaire was directed at four focus groups within each of the hospitals participating in ESEP. These were Chief Executive Officers, Emergency Department Directors and Nurse Unit Managers, bed coordinators and personnel from the Emergency Department floor. A total of 101 staff responded. Emergency Department staff were generally accurate in their perceptions of performance changes. The most important factors effecting the changes were perceived to be changes in staff profile, management of patient flow through the department, changes in administrative policies and changes in work practices. Staff perceived that patient care has improved by 10% since 1995 and that ESEP has contributed 8% of this improvement. Staff have perceived improvements in ESEP performance indicators consistent with actual changes. The possible mechanisms by which these changes have occurred are presented and discussed. Factor analysis indicated that changes perceived to be most likely to result in improvements were: changes in staff profile (seniority), managing the flow of patients through emergency departments, changing administrative policies, changes in work practices and changes in staff numbers. Improvements in patient care were considered partly due to ESEP. In addition, ESEP has raised awareness of quality management issues.