Idiopathic pulmonary fibrosis (IPF) represents a particularly aggressive disease, the aetiology of which still remains unknown. The natural history of the disease often leads to respiratory failure and death, with a mortality rate greater than some cancers. To date, no management approach has proven to be efficacious for the treatment of this disease. IPF has been characterised as an 'epithelial-fibroblastic disorder', characterised by abnormal wound healing with excessive fibrosis and minimal inflammation. These emerging data have focused attention on antifibrotic drugs. Interferon-gamma1b (IFN-gamma1b) has recently been proposed as a promising candidate for the treatment of IPF. The reason for this is that IFN-gamma1b has the ability to modulate the Th1/Th2 imbalance and to suppress fibroblast activation. The view that IPF is untreatable at present requires reconsideration, as improved survival has been suggested in three controlled trials of IFN-gamma1b in IPF therapy.