A new entity characterized by pancreaatic insufficiency and bone marrow hypoplasia is described. The first three patients presented in this report had been followed in our cystic fibrosis clinic because of pancreatic insufficiency. These children did not develop respiratory tract difficulties and had normal sweat tests. The hematologic features included anemia; thrombocytopenia, and neutropenia. Attempts to correct all the hematologic abnormalities were unsuccessful. A biopsy of the pancreas in one case revealed intranuclear and intracytoplasmic inclusion bodies. This entity should be suspected in infants who fail to gain weight, have abnormal stools, and neutropenia, as well as those children who are thought to have cystic fibrosis diagnosed on the basis of pancreatic insufficiency with normal sweat electrolytes. Since three patients were observed from one family, it is felt that this is a genetically determined entity.