Foreword to the Third Edition A TribuTe To MeMories And ConTribuTions of russell l. ACkoff To design Thinking The grand old man of systems sciences, my dear friend of the last 40 years, is no longer with us. Russell Ackoff left us, unexpectedly, on October 29, 2009, due to complications from hip surgery. Just a week prior, we had a beautiful discussion about the resurgence of the same set of old interactive problems. We also discussed how the growing concerns with frequent market bubbles, faulty business models, challenges of globalization, blind pursuit of efficiency at any cost, stubborn unemployment, surging deficit, the state of public education, and an increasingly polarized society have created an overdue doubt in the minds of many that the existing conventional tools and the dominant growth paradigm may no longer be capable of dealing with the emerging complexities of our time. Sharing these concerns, we talked about how to make systems thinking more accessible to a larger group of practitioners. In this context and considering the current surge of interest in design