The Axial Offset Anomaly (AOA) is a major impediment to increases in reactor fuel performance preventing PWRs from operating with even more efficient core designs than they are at present. It is a phenomenon where boron compounds such as lithium-metaborate and nickel-boroferrite concentrate and precipitate during reactor operation in corrosion products deposited on high-duty fuel assemblies at subcooled nucleate boiling conditions and cause the reactor neutron flux and core axial power distribution to deviate from the predicted distribution. The purpose of the present work is to describe the...