Money. Intimacy. Disciplining children. These are issues nearly all married couples argue about. But happy couples tend to approach these conflicts differently from couples who are constantly arguing. They opt to focus on matters that are easier to solve.

It all comes down to choosing your battles wisely, a new study finds. Researcher Amy Rauer stresses its importance: “Being able to successfully differentiate between issues that need to be resolved versus those that can be laid aside for now may be one of the keys to a long-lasting, happy relationship.”

It's a good idea to avoid issues that challenge a partner's sense of competence or makes them feel vulnerable or embarrassed.

Rauer and colleagues from Northwestern University, the University of Missouri and the University of Michigan observed over one hundred couples who described themselves as happy and found that they rarely argued about issues they found difficult to resolve. Arguments tended to be on problems that had clearer solutions, such as the distribution of household chores and how to spend leisure time.

People avoided quarreling over their partner's health behaviors and over physical intimacy. These issues can be more difficult to address because they often challenge their partner's sense of competence or make them feel vulnerable or embarrassed, leading to even more conflict.

When couples ranked their most serious issues, intimacy, leisure, household, communication and money topped the list, as well as health for older couples. Jealousy, religion and family ranked as the least serious.

“Focusing on the perpetual, more-difficult-to-solve problems may undermine partners' confidence in the relationship,” Rauer, an associate professor in the Department of Child and Family Studies at the University of Tennessee, Knoxville and director of its Relationships and Development Lab, said. “If couples feel that they can work together to resolve their issues, it may give them the confidence to move on to tackling the more difficult issues.”

One group studied was in their 30s and had been married an average of nine years. The other group was in their 70s and had been married an average of 42 years. The couples who were married longer reported fewer serious issues and argued less overall.

Apparently, they had learned to pick their battles wisely.

This is consistent with previous research suggesting that older partners may prioritize the positive aspects of their marriage and decide that some issues are not worth the argument.

An article on the study appears in Family Process.