There have been few reports published in English on emergency medicine (EM) in Japan; the main reason for this is that the concept of EM was different in Japan from that in western countries. In the 1960s, legislation was passed in Japan that implemented emergency medical services, and emergency hospitals were designated by the government. There were no emergency medicine specialists, and so surgeons/physicians without specialist training in emergency medicine provided care to emergency patients (the multispecialist-type model). The Japanese Association for Acute Medicine (JAAM), an academic society for emergency physicians, was founded in 1973. In its pioneering days, this association focused mostly on trauma/burn care and also influenced policymaking. In 1977, the government built emergency medical service centers (the ICU-type model) and reorganized all emergency medical facilities into three levels. With the aging of society, the number of non-trauma patients presenting at hospitals, especially in the elderly population, has increased and has resulted in some cases of refusal by hospitals to accept emergency patients. A new postgraduate medical education curriculum was legislated in 2004 that mandated EM training for all postgraduates and encouraged reinforcement of emergency departments in teaching hospitals. The JAAM established a committee to promote the ER-type model of EM in 2003. By 2007, more than 150 JAAM-affiliated hospitals had implemented this type of EM. In conclusion, emergency medicine in Japan is currently based on a mixture of three models: the multispecialist-type, the ICU-type and the ER-type models.