The U.S. Army has long used the staff ride as a tool for professional development, conveying the lessons of the past to contemporary soldiers. Antietam is ideal for a staff ride, since a continuing goal of the National Park Service is to maintain the site in the condition in which it was on the day of the battle. The purpose of any staff ride is to learn from the past by analyzing the battle through the eyes of the men who were there, both leaders and rank-and-file soldiers. Antietam offers many lessons in command and control, communications, intelligence, weapons technology versus tactics, and the ever-present confusion, or "fog" of battle. We hope that these lessons will allow us to gain insights into decision-making and the human condition during combat. Includes 15 maps, 4 tables, 18 illustrations, explanatory sections on artillery and logistics as well as order of battle information. (Originally published by the Army's Center for Military History)