Dysgammaglobulinemia type I (deficiency of IgG and IgA with normal or elevated IgM) is frequently associated with severe neutropenia, undue susceptibility to infection and recurrent or persistent mouth ulcers.1 The mechanism underlying the neutropenia is unclear and gamma-globulin treatment has in all but two cases2,3 failed to increase absolute neutrophil counts. This report describes the correction of severe neutropenia in a patient with dysgammaglobulinemia type I after administration of unusually high doses of gamma-globulin. It is shown that treatment is only effective if serum IgG levels are maintained above the level necessary to keep individuals with hypogammaglobulinemia and normal neutrophil counts free of infection.