As a psychologist and sexologist, we've spent a combined 50 years studying what makes relationships successful.

One misconception many people have is that happy couples argue less. But that's not the case; they just argue more effectively.

When we work with couples who seem to be making no progress in their disagreements, we often suggest they declare a truce and make a plan to communicate better. They each write down what has been bothering them about the other person (and about the relationship itself).

In order for this to be effective, couples must establish certain rules of engagement about how these problems will be shared and discussed. 

Communication rules of the most successful relationships

If you already use these rules of engagement when you argue, your relationship is more successful than most:

1. We will be honest but not cruel.
2. There will be no name-calling or shaming.
3. Our goal will be to resolve this so we can move forward.
4. We will not leave the conversation, but it's okay to ask for a 20-minute break.
5. We will assume that we both want the same things — to connect and to improve our relationship.
6. We will take the stance of "it's you and me against the problem, not you against me."
7. We will try to use "I feel" statements instead of blaming each other.
8. We will state positive needs (e.g., "I need to feel closer to you.").

It's critical for you and your partner to agree that the rules of engagement include tact as well as truth. This will help the both of you get to the root of your problems without severing your emotional connection.

When couples can give each other the space for their opinions to be fully stated, and then ask questions about those opinions, as opposed to just insisting on their own opinions (or leaving the scene), softer feelings have time to surface.

These warm feelings are the glue that hold successful couples together.

Jessica Griffin, PsyD, is a professor of psy­chiatry and pediatrics at the University of Massachusetts Chan Medical School. She is also the co-author of "Relationship Rx: Prescriptions for Lasting Love and Deeper Connection." Follow Jessica on Twitter and Instagram.

Pepper Schwartz, PhD, is a sexuality expert and co-author of "Relationship Rx: Prescriptions for Lasting Love and Deeper Connection." She is a professor of sociology at the University of Washington in Seattle, where she created the Pepper Schwartz Fellowship on Intimate Relationships and Sexuality. Follow Pepper on Twitter and Instagram.

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*This is an adapted excerpt from "Relationship Rx: Prescriptions for Lasting Love and Deeper Connection″ by Jessica Griffin and Pepper Schwartz, published by Rowman & Littlefield Publishers. Copyright © 2023 by Jessica Griffin and Pepper Schwartz.