I wrote this book with the intention of sharing core investment concepts that I thought might be informative for the majority of investors. My target audience was anyone interested in a thoughtful analysis of asset allocation. This applies to the entire spectrum, from novice to expert. Consequently, an indispensable part of the process was to seek honest feedback from a wide range of people.

The first thank-you goes to my friends at Bridgewater, the organization that pioneered many of the core concepts presented in this book. Ray Dalio, Seth Birnbaum, David Gordon, and Parag Shah were invaluable supporters. I am grateful to each of them for introducing me to these ideas and providing essential feedback. This group of special individuals ultimately inspired me to accept the challenge of writing this book and publicly sharing these important concepts.

I am grateful to Bill Lee, a true expert in the balanced portfolio concepts, for writing the foreword and taking the time to discuss these ideas with me. We share a similar passion for investing, and I am so fortunate to have met him through this process.

Charles de Vaulx, one of the most successful investors in the world, has expressed particular interest in these topics. He and I have spent countless hours debating the merits and potential flaws of the approach. He offers a unique assessment because of his financial expertise, and perhaps even more importantly, his intellectually curious and naturally skeptical nature.

Sam Lee from Morningstar offered suggestions that incorporated his experience with many of the concepts presented here. I am appreciative that he took the effort to share detailed, thoughtful comments that materially enhanced the final manuscript.

I would also like to acknowledge Fran Kinniry (Vanguard), Rob Arnott (Research Affiliates), and Dr. Vineer Bhansali (PIMCO), three investment industry giants, for reading through the manuscript and taking the time to provide insightful input.

Other financial experts, who I also consider good friends, were kind enough to dive into the manuscript and provide an indispensable peer review. David Hou, Ben Inker, Wendy Malaspina, Nick Nanda, Larry Kim, and Ron Kutak enthusiastically pored over the manuscript and gave advice that made the final book a clearer communication of the core concepts. Peter Joers, a founding partner at Greenline Partners and a former senior professional at Bridgewater, took the time to read every word and make valuable suggestions. I must thank Damien Bisserier, my trusted friend and business partner, for all his support and feedback from the very beginning of this prolonged journey until the final review.

I would like to express my gratitude to the many colleagues in the industry who also read the manuscript and offered comments. Each was successful in pointing out ways that I could more effectively convey the message. John Ebey, my longtime friend and mentor, graciously guided me through this book as he has throughout my career. My colleagues of more than a decade, Len Brisco, Sergio Villavicencio, and Michael Tidik, eagerly reviewed what I had written and assisted in making needed improvements. My uncle, Clayton Benner, has a remarkable ability to review all my writings with a fine-tooth comb to uncover and correct oversights. Thank you all.

Above all I wish to recognize my wife of 16 years, Danielle Shahidi, who offered a nonfinancial professional perspective and, most impressively, read the original manuscript multiple times cover to cover. I will forever be thankful for her candid remarks and for helping make the final product so much better than what I had originally put on paper. I must also acknowledge her undying support through this long process, which helped me build momentum at each trough.

Likewise, I appreciate the genuine understanding of my wonderful children, Michael and Bella, on all of those late nights and weekends when I was occupied with this project. Of course, my parents, without whom no opportunities at all would exist, are owed most of the credit for this work as well as any other contribution that I have made. Without the full backing of my family, there simply would be no book.

Finally, my team at Wiley deserves recognition for their patience, direction, and extraordinary efforts throughout this endeavor. I would like to express my deepest gratitude to Bill Falloon for giving a new author a chance. Meg Freeborn, Helen Cho, and Susan Cerra are extremely talented editors and were an integral part of helping me bring this project to fruition.

It has been a very long road from when I had an idea about this book until the time it was actually completed. I feel so fortunate to have had so much encouragement and help throughout this prolonged process and will remain immeasurably appreciative to everyone involved.