Life tables for 128 children with cystic fibrosis without meconium ileus, and for 43 cases with meconium ileus, have been constructed for the five years starting in 1964. These are compared with similar tables constructed for the preceding 20 years and show narrowing of the gap between the life expectancy of those entered at birth and at diagnosis, and a very obvious improvement in survival rate. It is suggested that this is due to earlier diagnosis and treatment.