War is the ultimate form of human relations. From a Christian and Jewish point of view, it negates the most important of the Ten Commandments: "Thou shallt not kill." Is it pure illusion to believe that war may be subject to legal rules? Was Cicero possibly right when he wrote inter arma silent leges (in war, the law is silent)? The horrors of wars in the last decades have made it clear that Cicero's approach would lead us to the ultimate catastrophe, simply because the destructive potential of modern weaponry is so overwhelming that we need rules governing warfare. This article intends to provide the reader with a brief introduction to the Law of Armed Conflict, its genesis, and its basic rules and principles with particular emphasis on rules regulating medical issues. Finally, we would like to show ways to implement Law of Armed Conflict in peacetime and during armed conflict. Where appropriate, reference is also made to the complementary body of human rights law and to standards of medical ethics.