Chronic granulomatous disease (CGD) is a primary immunodeficiency disease which results from absence of the NADPH oxidase in the professional phagocytic cells neutrophils, monocytes, macrophages and eosinophils. Deficiency of this oxidase renders the patient liable to infection by bacteria and fungi, and, as the name of the disease suggests, to chronic granulomatous inflammation. These patients present with a great variety of infections and other complications of their disease, which often tax the clinical and therapeutic skill of the doctors responsible for their care. Collectively we look after, or advise on the management of, over 100 of these subjects, and have developed experience in the diagnosis and management of the infections and other clinical problems they present. We thought that it might be timely to provide guidelines for their management based upon this experience. The numbers of patients are still relatively small, and the clinical presentations very varied, so it is impossible to provide clear statistical proof of the veracity of this advice. It does, however, reflect the working practise of the physicians caring for many of these patients in Europe.