Waiting time for public hospital care is a regular matter for political debate One political response has been to suggest that expanding private sector activity will reduce public waiting times. This paper tests the hypothesis that increased private activity in the health system is associated with reduced waiting times using secondary analysis of hospital activity data for 2001-02. Median waiting time is shown to be inversely related to the proportion of public patients. Policymakers should therefore be cautious about assuming that additional support for the private sector will take pressure off the public sector and reduce waiting times for public patients.