The chapter describes hemorrhage, blood transfusion and bleeding disorders. Hemorrhage can be classified as external, internal, arterial, venous, capillary, primary, secondary, reactionary, mild, moderate, severe, acute, and chronic. It is important to measure the volume of lost blood so that blood volume to be replaced can be estimated. Treatment of hemorrhage involves controlling of bleeding, and restoration of blood volume. Indication of blood transfusion, method of blood collection and its storage, blood grouping and cross matching, techniques of blood transfusion and its complications are described. Various fractions of blood and their uses are outlined. Various bleeding disorders and their management are described.