This book is a case study of two active agers who began this Active Aging journey when in their late 40's. Their understanding of how it might work, why it should work came in large part from their academic studies. Both were in professorial and consulting occupations with a strong orientation to public policy and its implications for the health of people. This book is also a study of how beliefs about diet, nutrition, aging, and lifestyles change over time. They lived this journey from 1984 or so until the present. At ages 86 and 88, they still live actively, continuing their research into the causes of diseases and how lifestyles can be designed to live a healthier and, as also occurs, a longer life. What did they study to inform this journey? First among many are exercise and nutrition. Now both McCool and Brown work out five or more days a week. The aerobic exercise stresses intervals. In strength training, time under tension makes the sessions productive.Other subjects given much attention include training for the brain. Indeed writing this book was a brain-boosting exercise. All of our eating is scrutinized for its impact on the brain, as is our exercise regimes. We are whole organic persons, not just a collection of parts. We are social beings; we are spiritual beings, and we are psychological and spiritual beings. All of these factors make for an Active Aging life designed to deliver excellent health for long life.Why write the book? It was for us a brain-building exercise and one focused on avoiding dementia, a scourge of the idle mind. It is also a robust case study of two health professionals who have not just researched the work on the subjects covered but have tested the ideas in their life. Other can learn from this experience. It is a sharing in the hope that others will benefit from reading this story and our learnings.