Phototherapy of the newborn is a common procedure in the neonatal ward. Different devices and lightsources are being used in the Scandinavian countries. In order to evaluate the safety and efficacy of a yet another new phototherapeutic device, the BiliBed, a randomised clinical, open cross-over study was undertaken. The study population comprised 22 newborn infants with non-haemolytic hyperbilirubinaemia. The effects of Bilibed on bilirubin elimination, fluid balance and restlessness during treatment were determined and compared to those obtained during conventional phototherapy. Heart rate and respiratory rate were used as a crude index of sympato-adrenerg tone during treatment. Both appliances were equally effective in reducing serum bilirubin concentration. Heart rate and respiratory rate were significantly lower during treatment with BiliBed. In spite of equal faecal/urinary output in conjunction with less ad libitum feeding volume, a trend towards better weight development was observed during BiliBed treatment. This may reflect differences in insensible water loss during treatment. The results suggest that BiliBed may be used without any disadvantages for the newborn compared to conventional phototherapy. Larger clinical trials are needed to determine its place in the clinical setting.