This article analyses the evolution over the last two centuries of career horizons for public works engineers -- or the whole of the various avenues of public and private sector activities in which public works engineers are present at a given time. Divided into three chronological periods, the overall picture shows that public works engineers have gradually enlarged their original working areas (construction and maintenance of transport communication for the state). Described with the aid of numerous tables, this spreading out concerns both the opening out onto new employers (from the state to private enterprise and local authorities) as well as onto new domains within the state (research, management, environment).