The role of parental occupational exposure in childhood brain tumors was investigated in a population-based case-control study grouping 251 cases and 601 controls from three European centers: Milan (Italy), Paris (France), and Valencia (Spain). Parental occupational exposure to solvents and polycyclic aromatic hydrocarbons (PAH) during the five-year period before birth was estimated using a job-exposure matrix developed earlier in the same countries. Odds ratios (OR) of brain tumors for each occupation and occupational exposure were estimated by logistic regression, adjusting for child's age, gender, exposure to tobacco smoke and ionizing radiation, mother's age and years of schooling, and center. The risk of childhood brain tumors rose when fathers worked in agriculture (OR = 2.2, 95 percent confidence interval [CI] = 1.0-4.7) and motor-vehicle-related occupations. In the latter group, the risk increased for primitive neuroectodermal tumors in particular (OR = 2.7, CI = 1.1-6.6). Astroglial tumors were more frequent among children of mothers in health services (OR = 2.2, CI = 1.0-4.9). Paternal exposure to PAHs was associated with an increased, but not dose-related, risk of primitive neuroectodermal tumors (OR = 2.0, CI = 1.0-4.0), and maternal exposure to solvents at a high level was associated with an increased risk of both astroglial (OR = 2.3, CI = 0.9-5.8) and primitive neuroectodermal tumors (OR = 3.2, CI = 1.0-10.3).