Urine samples were collected from 1,000 school children aged between 4 and 15 years. Twenty-eight children had significant bacteriuria, while 32 had significant pyuria. Seventeen pupils had both significant bacteriuria and pyuria. The study shows that although there is a positive association between pyuria and bacteriuria, the absence of pus cells in urine samples cannot be taken as evidence of absence of bacteriuria, nor can the presence of pyuria alone be considered as an indication of infection. Escherichia coli is the commonest agent in school children with significant bacteriuria.