This paper highlights the usefulness of international sources for historiographic research in Colombia, specifically the sources available in archives available in the U.S., and refers to some cases of documents used in publications made during the last two decades, particularly from the U.S. National Archive and the National Security Archive of the George Washington University Archive, and to the Freedom of Information Act under which both operate. Finally, it lets know the Colombian public about the availability of documents originated in those archives for the period of 1940-1953, facilitating their use by other researchers.