Among ill returned travelers to Schistosoma-endemic areas reported to the GeoSentinel Surveillance Network over a decade 410 schistosomiasis diagnoses were identified: 102 Schistosoma mansoni, 88 S. haematobium, 7 S. japonicum, and 213 Schistosoma unknown human species. A total of 83% were acquired in Africa. Unlike previous large case series, individuals born in endemic areas were excluded. Controlling for age and sex, those traveling for missionary or volunteer work, or as expatriates were more likely to be diagnosed with schistosomiasis. Sixty-three percent of those with schistosomiasis presented within six months of travel. Those seen early more often presented with fever and respiratory symptoms compared with those who presented later. One-third of patients with schistosomiasis were asymptomatic at diagnosis. Half of those examined for schistosomiasis were diagnosed with infection. Screening for schistosomiasis should be encouraged for all potentially exposed travelers and especially for missionaries, volunteers, and expatriates. Copyright © 2008 by The American Society of Tropical Medicine and Hygiene.