Japanese car makers were able dramatically to expand their share of the US car market in the seventies and eighties. This was partly the result of their own efforts and partly fortuitous. This paper examines why the US car makers of this period were vulnerable and how the Japanese were able to exploit their own technical and organisational strengths. An understanding of this key period in the history of Detroit’s ‘Big Three’ indicates why some two decades later the US companies found themselves on the brink of corporate ruin.