To reassess the schistosomiasis problem in Ngamiland and especially in Maun area 552 primary school children and 213 adult labourers were examined with urinalysis and rectal snip. Of the pupils 80.3% were found positive for S. mansoni and 1.4% for S. haematobium; of the labourers 35.7% were infected with S. mansoni and 0.5% with S. haematobium. There was no difference between the sexes; prevalence decreased by age. In Seronga village 102 pupils were examined; 69.6% were positive for S. mansoni. The decrease in prevalence in the higher age groups may be explained by recent introduction of the agent in the area.