Infection with human immunodeficiency virus (HIV) causes a progressive immunodeficiency, often manifested in adults by the development of infections with relatively rare, opportunistic organisms. However, in HIV-infected children, recurrent serious infections with common encapsulated bacteria, as well as recurrent minor bacterial and viral infections, may be early and frequent manifestations of HIV disease. The use of i.v. immune globulin (IVIG) has been shown to prevent infections in patients with primary immunodeficiency and in uncontrolled studies of HIV-infected children. This article reviews the problem of and immunologic predisposition for recurrent infections in pediatric HIV infection and reports on the use of IVIG for prophylaxis. Updated analysis from the National Institute of Child Health and Human Development IVIG Clinical Trial, a multicenter, double-blind, placebo-controlled trial of the safety and efficacy of IVIG for the prevention of infections in children with symptomatic HIV infection, is presented. Between March 1988 and January 1991, 376 children with clinical or immunologic evidence of HIV disease who were randomized to receive IVIG or albumin placebo were enrolled in this trial. In children with an entry CD4+ count of 200/mm3 or higher, IVIG significantly increased the time free from serious bacterial infections and significantly decreased the rates of minor bacterial infections and viral infections.