Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible fibrosing interstitial pneumonia of unknown aetiology that usually leads to respiratory failure and death within 5 years of diagnosis. Alveolar epithelial cell injury, disruption of alveolar capillary membrane integrity and abnormal vascular repair and remodelling have all been proposed as possible pathogenic mechanisms. This review summarizes our current knowledge of the abnormalities in vascular remodelling observed in IPF and highlights several of the cytokines thought to play a pathogenic role, which may ultimately prove to be future therapeutic targets.