A health survey was carried out among 8259 second- and fifth-grade schoolchildren living in three towns along the Israeli coast. The schoolchildren performed the following pulmonary function tests: forced vital capacity, forced expiratory volume in 1 sec, and peak expiratory flow, their parents filled out an American Thoracic Society-National Heart and Lung Institute health questionnaire. The aim of the survey was to study the impact of environmental and home exposures on the prevalence of respiratory conditions and on pulmonary function tests among Israeli schoolchildren. The health effects of exposure to passive smoking are discussed in detail. A trend of a higher frequency of reported respiratory conditions was found among schoolchildren whose fathers or mothers are smokers compared with children whose parents do not smoke. A statistically significant excess between 1.4% (for wheezing without cold) and 4.7% (for cough with cold) was found for children of smoking fathers; the excess for children of smoking mothers was between 1.6% (for wheezing with cold) and 3.6% (for cough with cold) compared with children of nonsmokers. A gradual excess in symptoms was found among children with none, one, and two smoking parents. Relative risks were found to be between 1.13 (for bronchitis) and 1.28 (for wheezing without cold) for children of smoking fathers, and between 1.24 (for asthma) and 1.41 (for cough with sputum) for children of smoking mothers, compared with 1.00 for children of nonsmokers. There was no consistent trend of reduced pulmonary function tests among children of smokers compared with nonsmokers' children.