Systems theory represents the core set of concepts or paradigm at the heart of systems thinking. These central ideas hinge around the difference between a wholistic synthetic-view of the world and an analytical-reductionist vision. This guide is designed to help you learn or teach this “systems paradigm” in a structured and coherent fashion. After giving an overview to systems theory we focus on four main themes, holism, emergence, relational thinking and process thinking. By the end of this guide, the student should be able to articulate the difference between the linear analytical paradigm and the synthetic holistic paradigm while being able to highlight the key features of both.