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 alveo- lar epithelial cells are risk factors for the develop- ment of IPF. There is also evidence for a genetic susceptibility. IPF is defined as the idiopathic vari- ant of Usual Interstitial Pneumonitis (UIP). Diag- nosis 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.