From the beginning of the century, autoimmune haemolytic anaemia (AIHA) was the first model of an auto-antibody mediated disease. Despite the variety of the clinical features, the diagnosis of AIHA provides few difficulties since the introduction of the popular Coombs' test. The clinical presentation of AIHA depends on the subclass type and on the thermal range activity of the causative auto-antibody, so that two main pictures occur usually: warm auto-antibody and cold auto-antibody types, the latter being less frequent than the former. In more than half the cases, AIHA is associated with another disease that must be considered more as the background of immune dysregulation than the cause of the disease. Systemic disorders, chronic lymphoid malignancy, primitive or acquired immunodeficiencies are the most common disorders associated with AIHA. Acute infections or drugs may give rise to acute transient AIHA. The clinical aspects and the links between AIHA and associated diseases are emphasised. No decisive advancement in therapy has arisen over the last decades. Some patients are still resistant to all therapeutic manoeuvres and may die. Much labour is to be done in order to discover more rational methods of therapy to restore a state of normal tolerance towards erythrocyte auto-antigens. Suppressing the production of pathogenic auto-antibodies by immunomodulation may be the first step of this task.