Liquid metal embrittlement is an unusual but industrially quite important failure mechanism. Although it has been recognized for about a century, the phenomenon is still poorly understood at an academic level, and industrial awareness of potential problems is limited. A review of the published reports of failures involving liquid metal embrittlement is presented, indicating that the problem occurs in a wide variety of circumstances and often in quite surprising situations. An overview of the research being carried out at the Cambridge University Engineering Department is also presented. This work is aimed at investigating the initiation and propagation behavior of liquid metal embrittlement cracks in cylindrical tensile specimens.