When Mel Cassidy first became curious about nonmonogamy, there weren’t many helpful resources. Most of the books focused on the transition from monogamy to nonmonogamy, but Cassidy, who goes by them/them pronouns, was “freshly divorced, hadn’t really dated as an adult.”
“I was winging it,” said Cassidy, who has since become a relationship coach who specializes in consensual nonmonogamy.
Recently, however, there has been an explosion of literature on the topic, including books about polyamory and other types of open relationships. And more people are interested, too: A 2023 Pew Research survey found that 51 percent of adults under 30 considered open marriages “acceptable,” and a 2016 study of single adults in the United States has shown that more than 20 percent have experimented with some form of consensual nonmonogamy.
But even as these relationship styles become more common, there are lots of details to figure out. Partners have to decide on the approach that works best for them. There are also sexual and emotional concerns to parse when bringing new partners into the mix, said Shadeen Francis, a sex and relationship therapist based in Philadelphia.
Good books can help nonmonogamous partners “develop compassion or positive empathy for one another,” said Marie Thouin, a dating and relationship coach and researcher based in the San Francisco Bay Area. They can remind you that “you’re not alone in your choice,” she added.
We spoke to more than a dozen relationship experts and researchers for their book recommendations — whether you’re in a nonmonogamous relationship or interested in exploring.
1. Polysecure by Jessica Fern
Insecurity often crops up in nonmonogamous relationships, Dr. Thouin said, and this title from 2020 addresses it through the lens of attachment theory, which examines how early relationships shape adult connections, especially romantic ones.
“It’s the first book I give to people,” said Michael Grey, a relationship therapist based in Irvine, Calif. Beyond helping people become more secure, he said, it also addresses how trauma can affect your love life. Your experience with trauma can influence how safe you feel within a relationship, he said, “especially in the context of nonmonogamy or polyamory.”
Ms. Fern’s book emphasizes that we have to work on our bonds, even when they’re spread among multiple partners. We shouldn’t “take each other for granted or go on autopilot,” Cassidy said. This is important, they said, because, ultimately, “it doesn’t matter what your attachment style is; what matters is how you choose to show up.”
2. The Ethical Slut by Janet W. Hardy and Dossie Easton
For Elyssa Helfer, a marriage therapist and sex therapist based in Los Angeles — and for many other experts — this book, published in 1997, was the first one they encountered on nonmonogamy. It “offers a comprehensive look at not just what nonmonogamy is, but how it can be practiced,” Dr. Helfer said, with a “big emphasis on consent and safety.”
The advice in this book, which presents tools for working through jealousy, applies to both those who are new to nonmonogamy and those who have been practicing it for a while.
It also “encourages people to explore their sexuality freely without guilt, shame or repression,” said Dr. Grey, helping people shed the stigma of having more than one romantic partner. “It’s about how to build trust and maintain integrity in your relationships,” he said.
3. Monogamy? In this Economy? by Laura Boyle
Ms. Boyle presents lots of good advice for addressing practical challenges that often arise when polyamorous partners are living with one another, said Kathy Labriola, a nurse and counselor in Berkeley, Calif.
Published in 2024, the book offers “the pragmatic side of things,” said Sam Allen, a clinical assistant professor at the Family Institute at Northwestern University. It can help readers think through choices like which partners live together and how to parent children, he said.
Though complications can arise, Ms. Boyle highlights the benefits of nonmonogamy, Dr. Labriola said. “Living with multiple adults means that the family has more people contributing income,” she said.
4. Opening Up by Tristan Taormino
For anyone who wants to explore more about the ethics of nonmonogamy, this is a great pick, Ms. Francis said. “Opening Up,” first published in 2008, examines topics like “disclosing your number of partners, your sexual health status, how you handle sexual health and how you introduce additional partners into your dynamic,” she explained.
Meant for couples who want to move beyond their dyad, the book is broken into three parts that tackle creating a relationship style and dynamic you want and sustaining it long term, said Jeremy Shub, a sex coach and educator based in Berlin.
“It’s not dogmatic or shaming, but offers a lot of invitations for reflections,” said Ms. Francis, who added that it’s a great book to read with your partner.
5. Love’s Not Color Blind by Kevin Patterson
Mr. Patterson is an educator who launched Poly Role Models, a series of interviews that highlight people’s experiences with polyamory. His 2018 book is a “brilliant sociological commentary,” exploring issues of race in nonmonogamous communities, said Dr. Helfer, who listed it as required reading for one of her courses.
“Stories about nonmonogamy tend to focus on young, fairly wealthy or middle-class white, cisgender people, in particular, and white heterosexual people,” Ms. Francis said. “To see yourself reflected in a narrative that is outside of that,” she added, “is an invitation to consider the ways that race and ethnicity and identity impact the ways that we date, the ways that we build communities, the ways that we love, and the ways that we create relationships.”
6. Multiamory by Dedeker Winston, Jase Lindgren and Emily Sotelo Matlack
Written in 2023 by three educators who host the “Multiamory” podcast, this book addresses common issues that pop up in the early stages of nonmonogamy, Ms. Francis said. For example, many couples deal with logistical challenges like time management, which can be addressed by using shared calendars, she said.
The advice found in “Multiamory” extends beyond nonmonogamous relationships, offering “good communication tools for all relationships,” Cassidy said. The authors provide formulas and “microscripts,” that couples can use to talk about issues that arise. A script can be “really helpful in having difficult conversations,” Cassidy explained. “It can empower you with a little more courage.”
