Anion Exchange Membrane Water Electrolyzers In article number 2404479, Nelson Y. Dzade, Deok-Yong Cho, Chan Hee Park, and co-workers introduced FeMn(NbTa)2O6 columbite as a novel, high-performance electrocatalyst for anion exchange membrane water electrolyzers. In-situ XAS and DFT analyses reveal that Fe/Mn sites exhibit higher oxygen evolution reaction activity due to reduced overpotentials and favorable O* to *OOH energetics. The Nb/Ta sites within the AB2O6 framework facilitate charge transfer, lower activation barriers, and enhance stability. FeMn(NbTa)2O6 columbite demonstrates remarkable durability and efficiency, matching the performance of Pt/C-RuO2 catalysts, offering a promising alternative for sustainable hydrogen production.