This paper considers key cases of karoshi (death from overwork) and their effects on reform of standards for granting workers’ compensation payments. If work is recognized as cause of death, Japanese law provides state support for victims’ families, recognition which aids them in suing employers for damages as well. Since the first cases of karoshi were “diagnosed,” Japanese courts, including the Supreme Court, have gradually recognized worker claims and expanded the conception of employer responsibility for worker health to include accumulated fatigue and mental health. In December 2013 a Basic Law for the Prevention of Karoshi began to make its way through the legislative process. However, at the same time, employment relationships have shifted from an authority-ranking style, in which the benevolence of superiors could be expected, to market pricing arrangements, in which benevolence cannot be presumed. The rise of karoshi and the medico-legal movement that uses litigation to secure compensation parallels the shift toward market-centered employment relationships. These two historical moments mark both declining expectations of traditional, particularistic benevolence and