Evidence of the unacceptably high incidence of patient harm associated with health care has resulted in patient safety becoming a major reform agenda. Despite significant investment by governments on strategies to reduce patient harm, confusion still exists on how to measure patient safety. While the goal of patient safety is harm prevention, most of the measurement focus has been on counting incident reports. The (ab)use of reported incident data to measure both technical safety performance (injury rates) and evaluate the effectiveness of safety improvement initiatives continues to confuse and mislead consumers, funders and providers of health care. This paper proposes a simple measurement framework for patient safety which balances the elements of: learning, action, performance, patient experience, and staff attitudes and behaviour. Application of this framework to current priority areas should be used as a basis for patient safety improvement at clinical unit, hospital, state and national levels.