Renewed interest in metallic fuels for liquid-metal fast breeder reactors (LMFBRs) has arisen for several reasons: The excellent performance demonstrated by metallic fuel, particularly at Experimental Breeder Reactor II; the demonstrated transient capability; the inherent compatibility with the sodium coolant; and the potential for superior breeding gain are primary benefits. The performance of metallic fuels in LMFBRs is summarized, then the state of the art for the metallic fuel types that are regarded as principal candidates for LMFBR applications are assessed. After listing the key issues that exist for metallic fuels, recommendations are made for resolving those issues.