Acute normovolaemic haemodilution (ANH) is a technique used to preserve a patient's owns red blood cells and reduce the incidence of heterogeneous blood transfusion. This paper describes the use of the technique in a dog and a kitten. A significant benefit of ANH can be shown in the canine case presented. The dog lost 1800m of blood during surgery but the haematocrit was only reduced to 33% 6 hours after the end of surgery. The kitten, however, did not benefit from ANH. It lost a small volume of blood during surgery and developed complications. This paper also describes some of the potential complications that may occur. To the best of my knowledge, this is the 1st clinical description of ANH in a dog and a cat.