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It's Not the Journey, It's the Preparation
What people look for in a marriage partner is another topic Finkel has investigated. "Basically they think, The sex is good, we love each other, we're good friends...," he says. "You'd go pretty far down the list before you'd get to 'We get in sync effectively.'" But he's learned that the ability to coordinate day-to-day tasks like shopping for O, The Oprah Magazine is a crucial component of a couple's happiness.

"Married partners are co-managers, and as the marriage progresses, it involves more logistical organization, especially if kids come," he says. "If you're not in sync with your partner, research suggests, you'll find yourself depleted, exhausted, and less effective, and if the problems are serious enough, it's difficult to imagine the relationship continuing to function effectively."

A courtship affords few opportunities to engage in the sort of knotty tactical tasks that fill a marriage. To test a relationship, Finkel suggests that you "throw it into challenge, so that if there's a problem, you can develop a system. Expose it to stressful coordination experiences. Instead of watching TV together or doing something comfortable, take a road trip that requires a lot of collaboration. Put one person in charge of six things, the other in charge of six other things, and then ask yourselves, 'How well do we do these things?'"