In summary, intravenous gammaglobulin appears to be a very useful treatment of immune haematologic disease. Almost all patients with ITP treated with IVIg will have an increase in their platelet counts lasting at least 2 weeks. Some of these patients will derive long-term benefit from the IVIg and many can maintain their platelet counts by periodic single outpatient infusions. Patients with immune neutropenia are also likely to benefit by IVIg treatment which may be of particular benefit due to its not interfering with phagocyte function. RES blockade is a well-documented mechanism of action immediately after IVIg infusion and platelet antibody synthesis may decrease in some patients; IVIg does not appear to protect platelets from platelet antibodies.