This paper presents the significance and range for the application of blood transfusion in horses. The main objective of total blood transfusion is to help improve oxygen delivery to the tissues during anemia; nonetheless, it is considered a temporary lifesaving procedure that should be only used if necessary. The majority of transfused erythrocytes remain in the circulation for an average of 5 days (after cross matching), which is why bone marrow response to the anemic crisis is crucial to the overall recovery. The short life span of transfused cells is likely due to minor antigenic incompatibilities that could have been detected if blood-typing of the donor and recipient had been performed. Over 30 different erythrocyte antigens (alloantigens) consisting of eight blood groups have been identified in horses, accounting for more than 400,000 phenotypes. The possibility of identifying a completely compatible recipient is nearly impossible, but cross matching can help prevent severe transfusion reactions. The paper describes techniques for donor selection, blood collection and storage, ways of administration whole blood and blood products. A detailed description of possible transfusion complications and methods of treatment can prevent serious life threatening conditions.