He was noted in particularly for his work in Morocco and Turkey, where he created a number of comprehensive city plans for Casablanca,[2] Fes, Marrakesh, Meknes, Rabat,[3] and Istanbul, including transportation infrastructure and avenues with buildings, plazas, squares, promenades and parks.

In 1913, Hubert Lyautey, the military governor of the French Morocco invited Prost to work on development of major Moroccan cities: Fes, Marrakesh, Meknes, Rabat and Casablanca.

Back to France, Prost worked in 1923-1924 as a regional planner, developing a series of comprehensive urban plans for Côte Varoise in Western French Riviera.

In 1936, Prost was invited to Turkey by Mustafa Kemal Atatürk to develop a grand plan of Istanbul's redevelopment, and he stayed there for fifteen years.

It is not about creating a New City on a virgin land, but directing an Ancient Capital, in the process of complete social change, towards a Future, through which the mechanism and probably the redistribution of wealth will transform the conditions of existence.

In 1902, Prost made a design drawing of a national printing office in Italy and was subsequently awarded with the Prix de Rome scholarship.