Blood pressure (BP) determinations were made by three physicians in 1,554 healthy Israeli schoolchildren aged 5 to 14 years, of whom 783 wer boys and 771 were girls. Subjects were divided into four groups according to ethnic origin: Yemenite--560, North African--357, Iraqi-Iranian--246, and European-American--391. There were no statistically significant differences in either systolic (S) or diastolic (D) BP between ethnic groups or between sexes. Comparing our data with those compiled by the United States Task Force on Blood Pressure Control in Children, we found that the SBP tended to be lower than in American children by about 10 mm Hg, while the DBP was lower by about 7 mm Hg. An additional 4,460 children were examined by public health nurses, and 25 (0.6%) children were found to have a DBP above the 97th percentile for their age, and 46 (1.0%) children were found to have an SBP above the 97th percentile for their age. None of the children had an SBP or DBP exceeding the mean for their age by 2.5 SD, nor had any child any sign or symptom of high BP. Based on these results, we doubt the usefulness and cost-effectiveness of BP screening of children.