Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial pneumonia and a disease of the elderly. Cigarette smoking and longterm exposure to substances harming alveolar epithelial cells are risk factors for the development of IPF. There is also evidence for a genetic susceptibility. IPF is defined as the idiopathic variant of Usual Interstitial Pneumonitis (UIP). Diagnosis of IPF is complex and based on the exclusion of other diseases associated with an UIP pattern. The only cure is lung transplantation. In the last years there was a breakthrough in the treatment of IPF. With pirfenidone and nintedanib there are now two compounds approved for the treatment of IPF.