Idiopathic pulmonary fibrosis (IPF) is an under-recognised, rare, progressive disease of the lungs with unknown aetiology and high mortality. The currently advocated pathogenic mechanism is represented by progressive multifocal fibrosis. It is diagnosed based on clinical, radiographic, physiological and histopathological criteria. Existing therapeutic guidelines recommend anti-inflammatory and immunosuppressive combinations, despite proven limited efficacy. There is no therapy approved specifically for IPF, but several antifibrotic agents are currently under development for this indication. Pirfenidone is an antifibrotic agent potentially effective for IPF therapy, and preclinical and available clinical data support its use in IPF. Future clinical studies are expected to provide more consistent information on survival benefit, lung function and health-related quality of life.