The application of microdialysis for neurochemical monitoring in neurosurgery and neurointensive care is rapidly expanding in a number of clinical centers around the world. In order for microdialysis to become a future routine method in these clinical settings a number of problems, outlined in this communication, must be solved by the clinical researchers and the commercial companies. Regardless of the future success as a routine method, it is already obvious that microdialysis will be an important clinical research tool for years to come, providing new important insights into the pathophysiology of acute human brain injury.