QUIET STRENGTH

To be published by HarperOne in March of 2026

Revered meditation teacher and licensed psychotherapist Margaret Cullen reveals scientific breakthroughs and spiritual intersections that demonstrate how the power of equanimity allows us to live more fully, with balance and wisdom.

We are facing complicated and untenable predicaments—climate change, political division, global conflict—that are beyond our control, which often results in feelings of powerlessness and resignation, or disconnection and bitterness.

Drawing on decades of mindfulness practice and teaching, Margaret Cullen offers contagious enthusiasm about the groundbreaking discoveries focused on a virtuous habit that has been hiding in plain sight for over two thousand years: equanimity. Equanimity is characterized by non-reactivity and clear seeing and has the power to help us navigate the biggest dramas in our lives—not by ignoring them (or reacting in more fiery ways) but by being present with, and open to, all the very real struggles of being human without being hijacked by them. Equanimity is a profound and powerful force that can transform our responses to the events of our lives and in the world at large—and effect change inside our hearts and in all our interactions.

Featuring guided meditations, cutting edge research and fascinating insights from experts across a range of fields, Quiet Strength sparks curiosity and engagement with the practice of equanimity.

"In shaky times, Margaret Cullen helps us find an unshakeable inner balance. She integrates science, deep wisdom, and many practical tools into a roadmap and handbook for navigating our turbulent world. Throughout, her kindness shines through. In every page, she’s a friendly, good humored, and encouraging companion helping us to become less stressed and anxious, and more rested in our own calm strength. Truly, this is a masterwork, and it’s needed now more than ever."

- Rick Hanson, PhD, author of Buddha’s Brain, Hardwiring Happiness, and Resilient
"Equanimity is to feelings what mindfulness is to presence—and Quiet Strength is the rare book that makes this truth come alive. With wisdom, clarity, and warmth, Cullen invites readers on a transformative journey, revealing equanimity not as dry neutrality, but as a wellspring of empowered engagement. In a world that often feels like it’s spinning faster than time itself, this book offers a steady anchor: the quiet strength of balance, presence, and inner calm. A must-read for anyone seeking resilience, clarity, and peace in the midst of change."

- Amit Sood, MD, CEO of the Global Center for Resiliency and WellbeinG
"In Quiet Strength, Margaret Cullen explores the profound meaning and far-reaching benefits of equanimity—an often overlooked quality so essential to our well-being. True to the spirit of equanimity itself, Margaret draws from a wide range of traditions to illuminate its nuances, challenges, and methods of cultivation. With warmth and wisdom, she offers a path to this open-hearted balance of mind—so urgently needed in these polarized and turbulent times. The courage of her inquiry and the depth of her understanding infuse every page of this transformative work. Highly recommended."

- Joseph Goldstein, author of Mindfulness: A Practical Guide to Awakening
"Quiet Strength is the mindfulness book of the decade—and the only book that focuses on the magic-like quality of equanimity. Margaret Cullen, one of the nation’s most deeply respected mindfulness teachers and pioneers, has created a beautiful masterpiece, integrating wisdom and the emerging science of the mind, with remarkable stories, humor and humility, sharing a generous path that is true salve for the soul."

- Elissa Epel, University of San Francisco professor and New York Times bestselling author of The Telomere Effect and The Stress Prescription
"Quiet Strength arrives at exactly the right moment. Drawing on decades of teaching, research, and deep practice, Margaret Cullen offers a clear, wise, and practical guide to cultivating equanimity—the steadiness we need to meet life’s challenges with clarity, compassion, and resilience."

- Jack Kornfield, author of A Path with Heart
"Equanimity is a truly excellent quality. In Quiet Strength, Margaret Cullen splendidly describes equanimity as 'vulnerable without weakness' and 'wise without detachment.' She shows us that equanimity isn’t about escaping life—it’s about meeting all of it with clarity, steadiness, and delight. This is a book written with heart, wisdom, and enough science to please an old engineer like me."

- Chade-Meng Tan, international bestselling author of Search Inside Yourself and Buddhism for All
"Weaving decades of personal practice with the wisdom of teachers spanning spiritual traditions, Cullen's Quiet Strength adds richness and depth to the exploration of equanimity, making it accessible to all, regardless of one's background or religious beliefs."

- Sharon Salzberg, author of Lovingkindness and Real Life
"As a neuroscientist, I was particularly intrigued by Margaret’s reporting on the science of equanimity. She weaves together perennial wisdom, compelling stories shared with real vulnerability, and practical tools drawn from her decades of meditation practice and teaching. This book not only offers a clear and insightful exploration of equanimity, it provides a way into it. The result is a guide that feels both timeless and urgently relevant. You’ll want to read it slowly and to return to it often."

- Amishi Jha, neuroscientist and author of Peak Mind
"In this clear and compassionate book, Margaret Cullen explores equanimity as a powerful inner resource for navigating life’s challenges. Grounded in science, philosophy and contemplative wisdom, Cullen offers a practical path to emotional balance and clarity. Both accessible and profound, this book is an essential guide for anyone seeking stability, insight, and resilience in uncertain times."

- Kristin Neff, author of Self-Compassion and Fierce Self-Compassion