Cystic fibrosis is a genetic disease occurring more frequently in Caucasians. The cystic fibrosis gene, cloned in 1999, codes for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Dysfunction of this protein leads to the clinical manifestations of cystic fibrosis, mainly lung disease and exocrine pancreas disorders. The pathophysiology of the respiratory component is quite complex, basically related to major and excessive inflammatory processes and to early microbial colonization. Respiratory physical therapy is a key element to management of the respiratory disorder. Antibiotic treatments should be adapted to the bacterial ecology, mainly using antistaphylococcal and antihaemophilus drugs initially, then directed against Pseudomonas aeruginosa. Other drugs including inhaled antiinflammatory drugs are currently in the evaluation stage. In addition, nutritional care and correction of pancreas insufficiency are necessary. The diagnosis of this disease must be made early although systematic neonatal screening is not proposed. Early diagnosis is necessary for improved care and prognosis. Currently, median survival is 29 years. This survival time should probably improve with better understanding of the pathophysiological mechanisms and new therapeutic perspectives.