This book is a testament to the value of smarter collaboration. As coauthors, we drew on our very different professional experiences to enrich the ideas and challenge each other. But far more than that, we were blessed with an enormously diverse, generous community of people who really, really believe in the power of collaborating across silos to generate more innovative, inspiring, and productive outcomes. These are people—probably just like you—who have seen that we can achieve so much more, in such better ways, when we value the inputs of a highly diverse set of people, bring in those voices at just the right time, and throw ourselves into the sometimes vulnerable space of smarter collaboration. We can only begin to thank those contributors here.

Let’s start with some people whose unique inputs made a big difference to our research. We are grateful to Christa Gyori for her keen insights and generosity in making introductions. Heidi’s colleagues at Harvard Business School and Harvard Law School provided valuable insights and challenge throughout our research process, as did all the members of our ongoing research symposium GroupsGroup. Special thanks to Dr. Ruth Wageman for continuing that forum, which was begun by our revered, late mentor Dr. J. Richard Hackman. Professor Rob Cross and Dr. Mark Mortensen, who coauthored prior HBR articles with Heidi, continue to be important sources of ideas and inspiration. Major thanks go to Claudio Fernández-Aráoz, Steve Immelt, and Laura Melchor McCanlies for providing valuable feedback on an early version of our manuscript.

Our deep thanks go to the people who directly worked with us on the manuscript and all its iterations. The indomitable Gardner & Co. team includes Cheryl Caruolo, Christine Dunne, Esteban Guijarro, Lea Haggarty, Csilla Ilkei, and Geoff Watkinson, supported by our fabulous interns Justin McMahon, Ana Sofia Moraskie, Allison Puglisi, and Mohammed Siraje. We also thank Joanna Wozniak for superb data crunching and Stephanie Bennaugh for expert research assistance. Steve Prokesch edited multiple HBR articles that underpin ideas in this book, and challenged us to sharpen our thinking at each stage. To Jeff Cruikshank, our developmental editor: thank you for your creativity, humor, patience—and pushing us to use the occasional exclamation point! Jeff Kehoe and the amazing team at HBR Press provided the perfect level of input to help us refine our ideas.

We are indebted to the many interviewees and others who directly added your ideas, data, experiences and network to this book. Whether we quote you by name or simply drew on your inspiring stories, you have been invaluable: Jennifer Artly, Diane August, Nitesh Banga, Ester Banque, Paul Barnett, Prof. Iris Bohnet, Jakob Bohnet, Ben Christensen, Tom Comery, Mark Dalio, Dr. Aaron Deykin, Leslie Dory, Philip Goodstone, Jason Hardgrave, Stuart Henderson, Portia Hickey, Donna Hicks, Dan Hoffman, Ambassador Stuart Holliday, Perry Hooks, Lisa Inserra, Michael Jackson, Michelle Jubelirer, Roberto Junguito, Ged Keogh-Peters, Martin Kingston, Denise Kruger, Helene Kubon Skulstad, James Lam, Eric Lee, Andrea Legnani, Carl Liebert, Tammy Lowry, Karen Lynch, Denis Machuel, Karn Manhas, Daniel Mauro, Dan Mearls, Kathryn Metcalfe, Matt Meyer, Jesper Michaelsen, Tangy Morgan, Tom Moriarty, Dr. Rebecca Newton, Rebecca Normand-Hochmann, Rob Ollander-Krane, Yvette Ostolaza, Nicole Petrie, Alex Poniewierski, Sharon Price, Steve Rader, Dr. Amrit Ray, Darrell Rigby, Mark Rivera, Tom Ruderman, Maria Salinas, Chris Shaida, John Shiel, Julie Thomas, Puru Trivedi, Jennifer Trosper, Steve Twait, Tamsin Vine, Dr. Ben Waber, Micah Waldman, Janet Woods, and Mitch Zuklie. We also appreciate all the coaches, facilitators, and consultants who became Accredited Partners in the Smart Collaboration Accelerator tool; your work in spreading and expertly applying these ideas is a vital part of our journey.

Writing this book would have been impossible without the unwavering love and support of our friends and family. Forgive us, dear friends, for not giving you individual shout-outs; we will continue to thank you in person. Our parents—Phyllis and Bill Gardner, and Carla and Greg Matviak—have encouraged and helped us over the years in too many ways to mention. Thank you for being our role models over the decades. Finally, our daughters Zoë and Anya have inspired, bolstered, tolerated, and sustained us as we started working on this book during Covid lock-down and continued since. A project of this magnitude has required some sacrifices on everyone’s part; we hope that the laughs along the way and knowing that this book pushes forward our shared passion for diversity and inclusivity make it all worthwhile.

In closing, we return (no surprise) to the theme of smarter collaboration. In the years since the initial book, Smart Collaboration, was published, literally thousands of people have helped us to understand the power of applying these principles. Across the planet, leaders of major companies, professional firms, and nonprofit organizations seized the ideas, found ways to activate them, and deepened our know-how along with them. Moreover, people at all levels of seniority wrote and called us, offering their own insights, queries, and tips. With this new book, we hope to supercharge this smarter collaboration movement. We invite you into our smarter collaboration community!