Louis Joseph Halle Jr. (17 November 1910, New York City – 13 August 1998, Geneva, Switzerland) was an American naturalist, author, U.S. State Department official, and professor of international studies in Geneva. Halle received his bachelor's degree from Harvard University in 1932. As a young man, he worked for a railway company in Central America and later with a publishing house in New York. For a year, he did graduate study in anthropology at Harvard, then explored boundary rivers between Guatemala and Mexico by mule and dugout canoe.