The purpose of this United States Army Judge Advocate General's Legal Center and School 2021 Edition of the Law of Armed Conflict Documentary Supplement (DocSupp) is to provide students and practitioners with a ready reference of collected materials relevant to the study and practice of national security law. Modifications are based on the curriculum at The Judge Advocate General's Legal Center and School, with a focus on plenary instruction provided to students in both basic and graduate courses, as well as more specialized instruction during electives and short courses. This volume has historically found its way to the field, informing the practice of judge advocates in both garrison and combat.