"My parents encouraged us to live together before we got married to make sure we were compatible," said one young lady.

While many well meaning people think that it would make logical sense that living together would give couples the chance to practice the skills needed for a lifelong, healthy marriage and increase the likelihood of choosing the right mate, the research shows that the opposite is true.

"Couples start living together because it is more fun and cheaper than living apart," said Dr. Scott Stanley, Co-Director of the Center for Marital and Family Studies at the University of Denver and co-author of the paper Sliding versus Deciding. "One partner may see cohabitation as a prelude to marriage. The other, often the man, may see it as something more uncertain as leading to the future," Stanley and colleague Dr. Galena Rhoades give this example in their paper.

For example, Bob and Mary are in love and have developed a strong bond, but they also have low confidence about their ability to succeed in marriage. Their reasons for doubt are based on things like both being children of divorce, being wary of making bad choices, problematic past relationships, etc. Mary is more inclined toward marriage than Bob, but both think that living together is a good idea. Mary is seriously considering marriage while Bob just likes the idea of spending more time with Mary.

"What this couple does not consider are the constraints that will increase greatly when they begin living together," said Dr. Stanley. "Things like sharing financial responsibilities make it much more difficult to end a cohabiting union. Breaking up can be complicated in a dating relationship, but it is usually much easier when compared to moving out and finding another place to live. This could be one of the key reasons why studies show living together does not provide the benefits most people think it does. If one of the partners is failing the test, it is still hard to drop the class."

Over time Bob and Mary end up having a child together. Their pathway into cohabitation was partly determined by doubts about their relationship. While the doubts have not gone away, the costs of leaving have increased.

"Bob and Mary eventually move on to marry, but with considerable reluctance on Bob's part," said Dr. Stanley. "A high risk marriage is born from an already high risk relationship. What many of the couples are saying without saying it is, 'I'm not ready to commit to you or sure that I really want to, but I like you and want to be near you for now, so I'll merely take some steps that will make it harder to break up with you while I'm figuring this out.'"

In many instances couples seems to slide into and through life changing transitions without clearly considering what they are doing thus they are sliding versus deciding. Dr. Stanley suspects that sliding through transitions will almost always be associated with higher risks. When a marriage gets tough, and most eventually do, partners who have slid through major transitions before that point may be more likely to be thinking , "I never really committed to you anyway," instead of being committed to working through the tough times. Without a vow of permanence, every major conflict is an occasion for insecurity. Unlike cohabitation, the marriage commitment provides the impetus to take a long-term perspective and work through conflicts.

"It is worthy of consideration that otherwise healthy and reasonably good relationships may sometimes fail as marriages because there never was an ideal clarity about each partner's commitment to the relationship," said Dr. Stanley.

If you are in a serious relationship and you don't know if you are ready to make the leap into marriage, instead of moving in together consider taking a class that will help you know if you have learned all of the different skills you will need to help your relationship last a lifetime.