Abstract
This article is rooted in the search for explanations for particular parallelisms and significant differences in the relative positions of the medical professions in Argentina and the USA in different health care services. My intention in this text is not to present an original historical account, as the empirical data about the performance of both professions that I uncover is not relevant in itself. Rather, this data serves as the object of a methodological exercise, which uses the information as a vehicle for a comparative analysis highlighting the impact of political institutions, dominant ideas on health and health care, and strategies of professional associations in the construction of each health care system, as well as the relative power of each profession in establishing the rules of the game which organized their activities throughout the 20th century.