The purpose of the study was to explore and describe the perceptions of critical care nurses' (CCNs) actual and preferred levels of involvement in significant decisions regarding patient care in critical care areas. A convenience sample of CCNs was recruited from two centres (one public and one private) and a researcher generated survey distributed to participants. Of the 131 questionnaires distributed, 90 were completed, giving a response rate of 68.7%. Results showed that, although most CCNs believed that they had important information to contribute to decisions relating to patient care, less than half felt that they were actively involved in such decisions. They were aware of the legal limits to their scope of practice but, despite this, most admitted that they made decisions beyond these limits. Approximately three quarters of the respondents thought CCNs should not be making decisions beyond legal boundaries. On the whole, CCNs wanted to be more involved formally and to have more power in decisions regarding patient care. One way forward is for the CCNs to have an advanced practice role.