OBJECTIVE:To examine the perceptions of sudden infant death syndrome (SIDS) and to describe the role of cultural beliefs and practices on child rearing amongst Thai mothers in Victoria, Australia. METHODOLOGY:In-depth interviews and participant observation conducted with 30 Thai mothers during 1995-96. RESULTS:SIDS was not known amongst these Thai mothers prior to migration to Australia. However, they were aware of SIDS when they gave birth here and all of them expressed fear about their baby's death. Due to this fear, most mothers tended to follow Thai beliefs and practices strictly to prevent death. These included breast-feeding, not leaving the infant alone at nighttime, placing the infant on the side or back to sleep, and bedsharing. It is considered that there are numerous evil spirits who may harm the infant, but some are benevolent and protect the newborn, such as ancestral spirits and the guardian angel of a child. Several Thai rituals are carried out to protect the newborn from ill health and death, including inviting the soul of the infant to reside in his or her body, and ritual clipping and shaving the hair of the newborn within the first month of life. CONCLUSIONS:Cultural beliefs, rituals and child-rearing practices help Thai parents to overcome their fear of SIDS. Hypotheses derived from Asian parents' child rearing practices may be useful in further SIDS research.