Abstract This paper reports the development of specialist genetic nursing in the UK and Japan. Between 1970 and 1990, significant technical advances in genetic testing occurred. These advances offered many families affected by genetic conditions more choices in diagnostic, predictive, and prenatal testing. It was recognized that genetic testing could significantly alter the life of the family and that supportive health services were required to accompany such testing. Nurses began to offer specialist services in this setting, but considerable professional development was required to ensure practitioners were competent. In the UK, the profession grew slowly over several decades. Concern to establish minimum standards of practice in this new professional setting culminated in the establishment of a set of competencies and a formal registration process. By comparison, in Japan, developments in genetic nursing have occurred over a shorter period of time, but minimum standards of competence already have been agreed upon.