English Abstract To measure platelet aggregation, within the framework of the development of an animal model of atherosclerosis, a Chrono-log whole-blood aggregometer was purchased. A survey to literature concerning platelet aggregationassays was conducted. In addition, the Bio Medisch Centrum of The State University of Limbury (RL) was consulted. This Centrum has got a lot of experience in measuring platelet aggregation in rat blood. The literature survey revealed several methods to measure platelet aggregation. In the manual of the Chrono-log aggregometer a method using human blood is described, but a method for animal blood is not presented. Initially, the method of the Bio Medisch Centrum will be applied. However, our practical problems associated with the use of this method will have to be solved first.