Abstract:Studies comparing particular medical specialties in different national settings have not appeared in the sociology of the professions literature. Consequently, little is known about how local contexts actually affect the professionalization process and medical specialization. Are certain determinants of specialization active in some countries and not in others? Can some determinants be said to be always active? Two recent independent studies of medical geneticists in, respectively, the UK and Canada present a unique opportunity to reflect on earlier social-theoretical discussions concerning the determinants of medical specialization in the context of country-specific organizational frameworks. Placed side-by-side, the two studies lend support to earlier research that emphasize, first, conceptual and technological innovations in medicine as driving specialty formation, and, second, the dominant position of physicians in the resulting division of medical labour. Beyond this, however, each study throws highlight on local influences as being important with respect to particular courses of action or inaction at the national and regional level. In the end, what appear to be coherent sets of diagnostic and counselling services from a unitary, global perspective can also be viewed as loose networks of resource dependencies, personnel, and organizations which can be re-configured within local health care delivery systems.