Here's the No. 1 'non-negotiable' habit for a successful relationship, says couples psychologist of 20 years

As a social psychologist, couples counselor and relationship expert, I've spent over 20 years working with thousands of individuals and couples.

The unfortunate reality is that many people don't know how to build and nurture loving relationships, and one area that's easily overlooked when things get busy is operations. In order to remedy this, I always encourage a weekly operations check-in to discuss upcoming admin duties.

I've found that it's usually these daily tasks, and each partner's perception of fairness, that ultimately causes a lot of conflict. So if you only have time for one check-in each week, make it this one. I would even go so far as to say that it's non-negotiable.

Cover any and all upcoming tasks

Once a week, sit down and talk about all the actual tasks that have to be done in order for the household to run smoothly in the coming week. Some of my couples call this the "Team Meeting." If you have children who are old enough to participate, include them, too.

No task is too small to go on this list. Grocery shopping, meal planning, meal prep, cleanup, laundry, drop-offs and pickups, plant watering, car maintenance, bill-paying — all of it has to be addressed.

Be realistic about your list and talk about the resources you each need. One week one of you might have more bandwidth, and the other less. Make sure to leave some room for things that erupt during the week unexpectedly as well. For instance, who will stay home if a child gets sick?

Over time, a lot of things become automatic and some tasks only have to be discussed when there's a change.

Bring up your pain points and get creative

This weekly meeting is also a good time to bring up things you'd prefer not to do. I call these your "pain points." If you really dislike washing dishes or making lunches, see if you can negotiate a different arrangement.

If neither of you wants to or can be on top of a task, maybe it's time to get creative or delegate it. For example, hire a dog walker or arrange a carpool for your child once a week while you go grocery shopping.

Make a list you can refer back to and adjust

Create a list that's visible to you both, like a shared online calendar with different color coding.

When my husband Pejman and I have our meetings, we add things in our calendars according to a color code that, among other things, indicates whether tasks are hard to move (i.e., they can only be canceled or interrupted if something very urgent comes up) or flexible (i.e., they can be moved around if need be).

You might end up finishing tasks from each other's list to make life easier for them because your half-day meeting on Wednesday got canceled — one reason why a shared list where tasks and updates are visible to both of you can be so helpful.

Be honest and transparent

Communicate your capacities and abilities as soon as possible to your partner. They may be disappointed or annoyed, but it will be far worse if you drop the ball completely without a heads up.

Annoyance and disappointment can be rectified, but if you're constantly dropping the ball, your partner will see you as unreliable, and the trust between you will be shaken. That's much harder to repair.

Sara Nasserzadehis a relationship expert with a PhD in social psychology. She has over two decades of experience working with thousands of couples. Her work has garnered global attention and has been featured in NPR, BBC, CNN and USA Today. She is also the author of "Love by Design: 6 Ingredients to Build a Lifetime of Love."

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This is an adapted excerpt from "Love by Design: 6 Ingredients to Build a Lifetime of Love," Copyright © 2024, Sara Nasserzadeh. Reproduced by permission of Balance Publishing, an imprint of Hachette Book Group. All rights reserved.