River health assessment and its supporting science have evolved to become a common component of water resource management. Broad-scale application of such assessments began using general indicators of health which are sensitive to many types of anthropogenic stressors. Assessments with such general indictors provide an overall evaluation of the success or otherwise of environmental management in protecting river health. However, there are additional management needs to diagnose the causes of any degradation and to guide what control activities are needed for restoration. Queensland Government has developed, applied and refined an approach to river health monitoring, assessment and reporting that provides this diagnostic capacity. It uses the principles of adaptive management and adaptive monitoring in a risk assessment framework which quantifies the likelihood and the consequence of defined stressors degrading river health. Conceptual models of the links between human activity and stressors and the stressors and their ecosystem responses guide this risk assessment. The stressor likelihood and consequence for a reporting area are quantified using available data, current literature and expert elicitation. A combination of the likelihood and consequence for each stressor provides the risk of that stressor to river health. Those stressors posing most risk are then selected for use in field based monitoring and assessment. Indicators of the intensity of stressors and their relevant ecosystem responses are selected according to the conceptual models and operational considerations. Final river health assessments combine and compare the initial risk assessment with the measures from field sampling to provide an overall picture of river health and a diagnosis of the stressors responsible for degradation. Recommendations for management to restore degraded health are made based on these results. This approach has been applied to many rivers in Queensland including the Warrego River catchment in the Queensland Murray Darling, used here to illustrate the approach.