Haemovigilance is a continuous process of data collection and analysis of adverse reactions which occur during blood transfusion and it is used to investigate their causes and outcomes to prevent their occurrence or recurrence. It is a powerful risk monitoring system for blood transfusion and its ultimate purpose is to improve the quality and safety of transfusion therapy. It also proves that blood transfusion is relatively safe compared with the use of medicinal drugs as these blood components have reached a high safety standard.