Book excerpt: The Army has recently embarked on massive advisory missions with foreign militaries in Iraq, Afghanistan, and elsewhere around the globe. This historical study examines three cases in which the U.S. Army has performed this same mission in the last half of the 20th century, In Korea during the 1950s, in Vietnam in the 1960s and 1970s, and in El Salvador in the 1980s. The Army thought it learned: The need for U.S. advisors to have extensive language and cultural training, the lesser importance for them of technical and tactical skills training, and the need to adapt U.S. organizational concepts, training techniques, and tactics to local conditions. These lessons are still important and relevant today. This is a print on demand report.