The blood supply chain starts with the blood donor and ends with the patient, but ultimately it is the requirement for blood by the patient that drives the chain and hence the number of blood donations required. Various factors affect the blood supply chain; the number of donors who are willing to donate regularly, seasonal factors affecting donation e.g. public holidays, the blood services ability to adequately predict the number of units of blood required throughout the year and to ensure that they do not overstock and therefore increase wastage, the clinicians' awareness of appropriate blood ordering and transfusion and the hospital laboratories ability to ensure sufficient stock yet have minimal wastage. It is essential that all staff working in each area of the blood supply chain is aware of their responsibilities to ensure minimal wastage of this freely given resource. Therefore education and training and data collection are important elements of the blood supply chain.