Idiopathic pulmonary fibrosis usually develops after 60 years of age, especially in men, leading to progressive exercise dyspnea. Median survival is about 3 years after diagnosis. This disease emerged in the middle of the last century and is linked to smoking. Mutations of genes encoding surfactant proteins and the telomerase complex may occasionally be present. International diagnostic criteria based on histopathology and computed tomography (CT) define the diagnosis as definite, probable or possible. Recent treatments (pirfenidone and nintedanib) have proven beneficial. Therapeutic advances warrant earlier diagnosis, based on Velcro crackles on pulmonary auscultation or interstitial opacities on CT screening for lung cancer.