A guide and exploration for newcomers and experienced Systems Thinkers alike. In Thinking Systems Robin Asby explores Systems Thinking from a process perspective and shows how this perspective generates new insights, particularly into the problems that we face in the stewardship of our planet. It explains how a process-based approach allows us to think differently and how it can be widely applied. Part 1 introduces Systems Thinking and the systemic process modelling of learning and managing. This is an up-to-date and accessible introduction for anyone interested in the theory and practice of Systems Thinking. Part 2 describes the effect of applying Systems Thinking in two key areas where problems of understanding exist: government and Quantum Mechanics. Whilst these two are far apart in the academic world, in each case surprising insights result from the systemic process approach.