Hair straighteners are a popular beauty product in the UK. An alarming rise in admissions to the Welsh Centre for Burns and Plastic Surgery, for burns caused by hair straighteners has led to this study. A thermodynamic study was also performed to look at temperature range and cooling profiles of these devices. Thirty-one cases were identified over a 32-month period, January 2003 to August 2006. Ninety-three percent (29 cases) were children with an average age of 4 years. The majority of burns were partial thickness to hands and feet, but 23% (seven cases) required admission and 10% (three cases) required surgical intervention. The hair straighteners reached a maximum temperature of 145 °C within 2 min of activation and took up to 7 min to cool below a temperature that would burn adult skin with a 1 s contact. Children and crawling babies are at particular risk from preventable burns from hair straighteners. The frequency of burns from hair straighteners is rising and even small burns to the hand can have serious sequelae and need to be treated in specialist centres. Health promotion and discussion with the industry is required to stop this new and increasing problem.