During the last years, as several historiographical contributions have demonstrated, a transnational perspective is especially relevant to understand crime and the establishment of police institutions in Latin America. From this perspective, this work analyzes circulation of knowledge of identification between Chile and Argentina during the end of the 19th century, and the beginning of the 20th. For this purpose, a series of documents from both countries were studied, which allows for the reconstruction of the circulation of knowledge and techniques, the interaction among experts on both sides of the Andes, and the way in which all these interactions shaped the implementation of anthropometry and fingerprinting in Chile. The article shows that, even if the development of identification in Argentina was quite influential in Chile, the identification in this country had a particular development that was even able to defy agreements reached within South American Atlantic countries.