**5. Conclusion**

The discovery of many early biomarkers of kidney injury has begun to shift the paradigm from assessment of change in filtration function to measurement of direct injury. Lest we throw the baby out with the bathwater we must recognise the complementary role of assessing both renal injury and renal function. Our techniques for assessing injury are still in their infancy, but show much promise. Our techniques for assessing function have a long history, yet, as we have shown, have room for improvement. In particular, we are learning to use appropriate surrogates of function, categorical or continuous, depending on the type of study we are conducting. We await the development of rapid, near "real-time" measures of function which are the missing link in enabling us to understand the temporal profile of injury in relation to functional change. We also look forward to an era of clinical trials which utilise the injury biomarkers discovered to date so as to properly test of drugs found to be effective soon after injury in experimental models.
