The present study had two main objectives: Firstly, to document the economic differences between‘ordinary’and‘aggressive’neurosurgical intensive care and secondly, to evaluate the medical benefits in relation to costs for different subgroups of head-injured patients. The study compares patients injured in traffic accidents and treated in the Department of Neurosurgery, University Hospital of Lund, during 1977-1978 (n=67) with similar patients treated during 1983-1984 (n=87) after introduction of more vigorous neurosurgical intensive care. The economic analysis was performed by means of the CRISE-method (Cost Related Index Score Evaluation) and all costs were related to the monetary value in 1984. Adoption of a program for‘aggressive’neurosurgical intensive care increased the costs per treated patient by about 46% (from 70.887 Swedish Crowns (SEK) to 103.452 SEK). Mortality decreased significantly after the change in intensive care and the cost per surviving patient remained virtually unaffected (131.928 SEK vs. 132.357 SEK). Further, after introduction of the‘aggressive’programme a larger proportion of the economic expenditures were spent on patients who ultimately recovered well. It is concluded that the increase in costs following introduction of a more vigorous intensive care programme in patients with severe traumatic brain lesions is very reasonable in relation to the documented medical benefits.