From the mid-nineteenth century to the early twentieth century, Professional Congresses sprang up in several countries. This article situates these events in the Universal Exhibitions and in Latin America, then to treat the specialties and social policies, especially in relation to childhood. It investigates the meaning of these encounters, locates them historically and questions the description that these congresses were essentially scientific activities, or even a practice begun by scientists, but reverberating into other spheres. The experts gathered to deal with proposals and standards for policies, legislation and social institutions, to organize the modern state and configure idealized urban societies and their institutions. Education had gained prominence as a factor in building the modern society. The circulation of ideas involved people engaged in intellectual functions, as well as ideas spread to the population at large, for whom the new products, institutions and cultural patterns would be designed.