A dahir (decree) passed in 1916 in the French Protectorate in Morocco consecrated the monopoly of modern medicine for European doctors, leaving Moroccans confined to the exercise of Arabic classical and traditional medicine. Two collectives of practitioners were especially threatened by the new legislation: Protestant missionary physicians and Moroccan modern doctors. The former had arrived in Morocco in the mid-19th century, especially but not exclusively from Great Britain. After settling in coastal towns, they established themselves in Fez, Marrakech or Tetouan, though not without difficulties and occasionally facing violent rejection. The latter were the product of various initiatives of medical modernization promoted or tolerated by the sultans. These usually implied training outside Morocco (in the military hospital of Gibraltar in the 1870s; in courses for medical auxiliaries in the Medical School of Algiers in the 1900s), though some attended the Tangiers School of Medicine created in collaboration with Spanish authorities in the late 1880s. Stays abroad, modern training or both things often resulted in various degrees of professional and social alienation. The menace that the 1916 dahir posed for both groups was essentially due to similar reasons: the lack of a formal or complete medical training; the non-French nationality and, therefore, the eventual competition with the embryonic French medical system; the mixture of religion and science that successfully appealed to Moroccan patients. In this presentation, we will provide a systematic picture of these collectives in the decades preceding the establishment of the French Protectorate in Morocco and, more specifically, the 1916 dahir. We will first identify the small number of individual doctors who integrated each group. We will later focus on how they engaged in transnational circulation and the impact of this on their professional and social identity in Morocco. Finally, we will analyze the outcome of the 1916 dahir for each collective and the arguments they presented to French authorities to defend their respective cause.