O-negative blood is a valuable asset as it can be transfused into any patient regardless of blood group and is therefore used in emergencies. However, O-negative blood is comparatively rare and therefore it must be carefully rationed. The Irish blood transfusion service is concerned that O-negative donors are being asked to donate too often and would like to reduce the amount of O-negative blood used, and in particularly reduce the usage of O-negative blood for the cases where it is not clinically necessary. The study group considered possibilities for a reduction of the O-negative blood usage in the Mid-West Area, where the current situation is particularly alarming. With the aim to quantify and minimize risks to patients in the Limerick region under a new regime in which less O-negative blood is stored at any one time, the study group explored the consequences of reducing the amount of O-negative blood stored at six local hospitals. The study group also explored the possibility of achieving a reduction of the inappropriate usage of O-negative blood by optimizing current routine practice and worked out practical recommendations for an improvement of O-negative blood management that can potentially reduce inappropriate use of O-negative blood to zero.