This article analyzes the emergence and transmission of the psychosocial development paradigm by PAHO/WHO to Latin America (1950-1990). It is argued that, although this discourse was programmatically consolidated within international organizations, its practical incorporation was at times limited by structural realities and the regional economic crisis. Using PAHO reports as a primary source, the study maps the evolution of priorities and programs, from the initial emphasis on early stimulation and mental retardation in the 1970s to the attempt at integration into primary care in the 1980s. It is concluded that the main legacy of this period was not a network of services, but rather the implementation of a conceptual framework that prepared the discursive terrain for the subsequent paradigm of children's rights.