Medical error and patient safety have become important issues. It is clear that medical error is more influenced by systemic factors rather than human characteristics. Communication patterns, in particular interruptive communication, maybe one of the systemic factors that contribute to the burden of medical error. Objective: An exploratory study to examine interruptive communication patterns of healthcare staff within an intensive care unit during ward rounds. Methods: The study was conducted in a tertiary hospital in Sydney, Australia. Nine participants were observed individually, for a total of 24 hours, using the Communication Observation Method (COM). The amount of time spent in conversation, the number of conversation initiating and number of turn-taking interruptions were recorded. Results: Participants averaged 75% [95% confidence interval 72.8-77.2] of their time in communication events during ward rounds. There were 345 conversation-initiating interruptions (C.I.I.) and 492 turn-taking interruptions (T.T.I.). C.I.I. accounted for 37% [95%CI 33.9-40.1] of total communication event time (5hr: 53min). T.T.I. accounted for 5.3% of total communication event time (56min). Conclusion: This is the first study to specifically examine turn-taking interruptions in a clinical setting. Staff in this intensive care unit spent the majority of their time in communication. Turn taking interruptions within conversations occurred at about the same frequency as conversation initiating interruptions, which have been the subject of earlier studies. These results suggest that the overall burden of interruptions in some settings may be significantly higher than previously suspected.