Abnormal neurological signs were found in 46 of 50 children and adolescents chronically sniffing leaded gasoline. These abnormalities resolved within eight weeks in all but one case. Exaggerated deep reflexes, postural tremor and evidence of cerebellar dysfunction occurred in a highly significnat number of patients. Forty-nine had blood lead levels greater than or equal to 40ug/dl. The mean blood lead levels were significantly higher in those with (a) abnormally brisk deep reflexes and (b) with evidence of cerebellar dysfunction, than in those without these findings. Five optional treatment regimes were employed and a classification was used, based on clinical findings, initial blood lead levels and the response to the calcium disodium edatate mobilization test. 39 patients received chelation therapy. These data suggest that neurological manifestations occur frequently in those abusing leaded gasoline and that chelation therapy has an important place in their management.