"A Systems Approach to Leadership" (SAL) is a methodology for creating sustained high performance in conditions of high complexity and uncertainty. SAL places the latest developments in Systems Science into an actionable method for use by everyday leaders. It enables leaders to develop themselves and their organisation (or part of it) quickly and effectively to achieve a competitive advantage in a complex and uncertain world. SAL consists of an integrated framework with an overall strategy of whole system development. Central to the framework is a practical method which can be used by any leader at any organisational level. Supporting the framework are a range of systems approaches and a set of foundational assumptions. SAL has been carefully researched and refined in extensive field tests where it typically delivers outcomes well above expectations.