Electronic verification of ABO compatibility (computer crossmatching) has been accepted as the crossmatching procedure for patients without clinically significant alloantibodies. Computer crossmatching offers several advantages over the immediate spin crossmatch and enables the setting up of a self service blood banking system. Self service blood banking saves manpower, improves crossmatch/transfusion(C/T) ratio and makes the maximum surgical blood ordering schedule (MSBOS) redundant. Blood banking service can also be provided at satellite hospitals without stationing blood banking staff there. We have also developed a novel self service system that does not require expensive computer hardware and networking.