After a brief survey of our present knowledge of Aldrich's syndrome a case of this strange illness is reported. The clinical picture—with eczema, thrombocytopenic bleedings and recurrent infections–and the almost complete lack of natural isoagglutinin in the patient's serum conforms with the descriptions given by other authors. However, persistent distressing vomiting, at least partially due to a relative stenosis of the pyloric canal, was a prominent feature in our case. It was not possible to establish the sex-linked, recessive inheritance originally demonstrated by Aldrich et al.; in fact, no other members of the patient's family have with certainty suffered from the disease. The possibility of an inborn error of immunoprotein metabolism is discussed, and the close genetic, clinical and serologic similarities in Aldrich's syndrome and various forms of congenital immunoparesis are emphasized. Analyses of the patient's proteins in serum, including immunoelectrophoresis disclosed a generalized hyperimmunoglobulinemia various abnormalities of the gamma globulins and an excess of three specific alpha2-globulins. The genetic serum type was found to be Gm(a÷).