The strategist of the 21st century soon will have to fulfil explicitly higher demands than those of the recent past. Increased complexness, volatility, but also insecurity, make a new definition of strategic competences for leaders necessary, regardless of their disciplines. Principle-oriented strategy doctrine, an integral education system of the past, is the key to equip the future strategist with a universal mind-set beyond the modular educational concepts of the latest decades. It involves a doctrine of thought which is based on the regularities of the social world – the strategic principles. It has been described by the most important classical authors of strategy as well as by well-known authors of the genres of the Mirror for Magistrates. In a triennial research project an up to now unique curriculum, which comprises four societies as well as 2.500 years of strategic history, was reconstructed, involving all the forgotten vocabulary of strategy. Considering the fact that the system of strategic principles contains 153 described patterns of action, the entire significance of the concept cannot be presented here. Some of the principles, such as alliance and disunion, appear trivial and thus everybody seems to know them; others, however, are sophisticated, and one needs some presence of mind to understand the underlying mechanisms. Additionally, in reality the principles are mostly interconnected which each other. The system of strategic principles carries on favouring no strategies or principles; only the situational context is authoritative for selection, as can be seen, for example, by the breakup of the Iraqi army. For this reason, it rather is a building set of manifold composite possibilities. Thus it becomes apparent how principle-oriented strategy doctrine can be established, and how it is to be understood. It reduces complexity, when the strategist separates patterns of action from the context and digests the factual situation on a level of principles. On this level, he uses an extremely elaborate repertoire of actions in order to create solutions meeting the regularities of the social world. Thus, principle-oriented strategy doctrine can be applied wherever individuals interact. Human action, especially strategic action, follows continually recurring patterns. The familiarity with patterns qualifies the strategist to intuitively apprehend even complex connections, and enables him to make unerring anticipations as well as equilibrated decisions. As a consequence, he will avoid wrong decisions, and thus reduce unintended effects, or so-called collateral damages, of his action.