Clinical research cannot be dissociated from medical practice. Every patient is unique but, most of the time, the symptoms observed can be associated with syndromes that have already been identified. On the other hand, the first colonial physicians are faced with diagnostic enigmas. Without being able to contact easily a colleague better-qualified and better-equipped, their observations and hypotheses are often consigned to reports which have never been published.

The first official and organized research activity goes through the overseas Pasteur Institutes thanks to the close collaboration between the Colonial Health Service and the Pasteur Institute of Paris. Medical societies are rapidly created in each territory. The research work of physicians and chemists are presented there and discussed. A journal which reports the work is published. Its diffusion plays a role in the continual training of isolated doctors.

After 1930, the Health Service establishes its own centres of research whose complete development will take place after the Second World War. In Africa, the Muraz Centre is devoted to the study of great endemics, trypanosomiasis in particular; the Marchoux Centre concentrates on leprosy; the Institute of Tropical Ophthalmology studies eye diseases; the ORANA, diseases due to malnutrition.

At the same time, the Pharo School opens its own research laboratories.

The colonial chemists are involved, from the beginning, in research activities concerning the identification of vegetables and minerals in these far-flung unknown territories. Their harvest of useful tropical plants is abundant and precious from an economic standpoint.