A case/control study of the association between parental occupation and childhood neuroblastoma was conducted. The cases consisted of 104 children diagnosed with neuroblastoma between 1970 and 1979 who were identified by a search of the records of the Greater Delaware Valley Pediatric Tumor Registry and the tumor registry of the Children's Hospital of Philadelphia. The referents consisted of 104 age and sex matched persons selected by random digit dialing of the same geographical area. The parents of the cases and referents were interviewed by telephone to obtain information on biodemographical characteristics and complete occupational histories. Odds ratios were computed for childhood neuroblastoma as a function of parental occupation with particular emphasis on employment in electrical, electronics, insulation, utility and printing jobs, and jobs with electromagnetic field exposure. The fathers of the cases had significantly less vocational training than the referent fathers. The educational backgrounds of the case and referent mothers were similar. The distribution of cases and referents among blue and white collar jobs was similar. Paternal employment in food product packaging and warehousing, farming, some electrical equipment assembly and repair, rubber processing and painting, and chemical related occupations was nonsignificantly associated with an increased risk of childhood neuroblastoma. The numbers of mothers employed in industrial jobs was very small. Among those who were, employment in textile and food product packaging, plastics packaging, and electronic or electrical product assembly was nonsignificantly associated with a risk of childhood neuroblastoma. The authors conclude that a clear association between parental employment in electrical, electronics, insulation, utility, or painting occupations, or jobs with electromagnetic field exposures and childhood neuroblastoma has not been established. The nonsignificant associations between paternal and maternal employment in some electrical or electronics related jobs and childhood neuroblastoma should be investigated further.