Latah, the Malayan hyperstartle pattern, has fascinated Western observers since the late nineteenth century and is widely regarded as a 'culture-bound syndrome'. Dr Winzeler critically reviews the literature on the subject, and presents new ethnographic information based on his own fieldwork in Malaya and Borneo. He considers the biological and psychological hypotheses that have been proposed to account for latah, and explains the ways in which local people understand it. Arguing that latah has specific social functions, he concludes that it is not appropriate to regard it as an 'illness' or 'syndrome'.