A vanillylmandelic acid spot test for screening infants for neuroblastoma was developed in cooperation with 11 health centers in Kyoto, Japan. In this system, the parent sends a filter paper spotted with the infant's urine at 6 or 7 months of age. From 78,331 infants screened during the six years from July 1973 to September 1979, four asymptomatic infants with neuroblastoma were discovered. Three of them have already completed their treatments and have recovered. The cost of screening 13,000 infants per year was $7,500. One false-negative test was encountered, as were a number of false-positive tests.