Patients with chronic lymphocytic leukemia (CLL) are at an increasing risk of infectious morbidity and mortality. Infections are generally due to bacteria and influenced by the degree of hypogammaglobulinemia; although, in more advanced stages of disease they may also be contributed by neutropenia due to bone marrow infiltration and/or cytotoxic therapy. Furthermore, defect in cell-mediated immunity appears to be a predisposing factor to infections in patients treated with newer purine analogues. Controversies surrounding the pathogenesis of infectious complications in CLL raise several questions on their management. Patients with advanced disease who receive cytotoxic therapy might qualify for antibacterial prophylaxis. Intravenous immunoglobulin (IVIG), although of scientific interest, may be of little relevance at the present time. The new growth factors should be tested in well-designed prospective studies.