Barack and Michelle do it. Brad and Angelina do it. John and Yoko did it. How?

As the divorce rate hovers near an estimated 50 percent in the United States, many blame career stress as a major cause of separations. But somehow some couples grow stronger, especially when they work together.

One couple who have worked together for nearly a decade in the stressful world of theater, producing Off-Broadway plays, has decided to share their secrets.  "In part, it is because we work together that our bond has strengthened after 10 years of marriage," says Jamillah Lamb, co-author along with her husband, David, of Perfect Combination: Seven Key Ingredients to Happily Living & Loving Together (www.acoupleoflambs.com).

The couple has worked together professionally in their stage company, Between The Lines Productions, Inc., for nine years. But the Lambs say even couples who aren't business partners are working together every day; because being in any relationship requires negotiating, compromising, and decision-making. Just think about the last time you had to decide whose mother's house you were going to for Christmas or where you were going to go for vacation or even which movie you were going to see last weekend.

"We get more opportunity to grow together because, between home and work, we're making 100 decisions a day instead of 10," Jamillah says.  The couple live by their guiding rule, "Love like kids, act like adults.  That means to love freely and completely, without a fortress around your heart, and behave responsibly," David says.

A crucial ingredient for any successful marriage is friendship, the Lambs say. Here are some of their tips:

• Enjoy life: Some couples won't go to theme parks until they have children. But letting one's inner child out to play with their partner's inner child strengthens a relationship's bond.
• Forgive the small stuff: No one is always right, and no one wants to be around someone who always needs to be right.
• Appreciate individuality: Everyone needs to have their own identity, including those in a long-term relationship and couples who work together. David enjoys his comic book collection, while Jamillah keeps a library of romance novels.
• Do not misdirect anger: In psychology, it’s called transference; dumping your bad day on someone else. It is poison for any relationship.
• Remember your love: Couples may fight, but guard what you say. There's no need for ugliness even when you disagree.

"Couples need to remember relationships take work, but they can also be a blast of fun," David says.

"Love is worth the sacrifice," they agree. "Today, with stories of celebrity couples walking away after only days of marriage and even more people living as though sacrifice is nearly a curse word, we say: It's worth the sacrifice. For us, it means that we are willing to give up something that we thought was valuable or important for something even more important: love and our happiness."

"Love is, in part, the acknowledgement and deep appreciation for another human being," Jamillah says.

"Couples should never take each other for granted," she advises. "In love, as in business, everyone wants to be appreciated. The simplest gesture can go a long way to help your significant other feel like they are making a significant contribution to your life, your family, or your business."