The harvest of wildlife through hunting, trapping and snaring is illegal in Vietnam but remains widespread and is understood to be the major threat to many species. Clandestine activities such as trapping and snaring, which are deeply embedded in the culture and economy, are difficult to investigate and this study is the first to carry out in-depth research into the illegal capture and sale of wildlife by a major ethnic group in Vietnam. The research focused on two villages of the Katu, a forest-dwelling people living close to the boundary of the newly created Saola Nature Reserve, and involved collecting data from a focus group, 30 semi-structured interviews with trappers, and a number of informal, unstructured interviews with local forest rangers, forest officers and village headmen. We find that trapping is widespread and motivated by financial gain and non-pecuniary benefits such as social esteem and enjoyment, rather than by poverty per se. Trappers’ awareness of wildlife protection law was low and animals were killed indiscriminately in traps and snares designed to catch a range of animal species. With demand for wildlife and wildlife products expected to increase we believe that new approaches will be required to protect threatened species in Vietnamese protected areas.