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This paper provides a comprehensive review of the recent research on the phase stability, point defects, and fracture toughness of AB₂ Laves phases, and on the alloy design of dual-phase alloys based on a soft Cr solid solution reinforced with hard XCr₂ second phases (where X=Nb, Ta and Zr). Anti-site defects were detected on both sides of the stoichiometric composition of NbCr₂, NbCo₂, and NbFe₂, while they were observed only on the Co-rich side of ZrCo₂. Only thermal vacancies were detected in the Laves phase alloys quenched from high temperatures. The room-temperature fracture toughness cannot be effectively improved by increasing thermal vacancy or reducing stacking fault energy through control of phase stability. Microstructures, mechanical properties, and oxidation resistance of dual-phase alloys based on Cr–NbCr₂, Cr–TaCr₂, and Cr–ZrCr₂ were studied as functions of heat treatment and test …