Do you know the number one factor couples cite as crucial to their satisfaction with their relationship?

That's right, it's good communication. There are so many issues couples can disagree about'money, children, in-laws, work'but whether or not these issues become problems depends on how well you can communicate.

If you have serious communication issues, you may need couples counseling. But if your relationship works most of the time, but you occasionally find yourself at a dead end when talking to your partner'or if you sometimes just find yourself saying, 'What can he be thinking?!''then improving your understanding of each other is the key to making your relationship even better.

We often marry people who are very different from ourselves, and this can be the perfect choice. If we find a partner who excels in the areas where we're weak, that can make for a great team. Problems can arise, however, when it comes to understanding each other's thinking. Here's an example:

David and Julie have been married for five years. Most of the time, their marriage works. David tends to be the forward-thinking partner; he's always looking at some new investment for the couple or dreaming up a home improvement project. Julie prefers to take care of the details. She's the one to pay the bills on time and make sure that the couple is prepared to take on all those projects that David dreams up. They make a good team, but sometimes Julie gets annoyed with David having his 'head in the clouds' all the time. David, on the other hand, feels like sometimes Julie is just too involved with mundane details, and can't see the 'big picture.'

How can we explain this couple's differences? There is a simple answer: personality type. Julie is a more concrete type; David is more abstract. According to the system of Myers-Briggs Personality Type, which is one of the most well-known and widely used personality theories in the world, Julie is a Sensor, while David is an Intuitive. Julie trusts what she can see; David trusts ideas. This is only one aspect of personality, however. There are four scales in total.

? Extroverted/Introverted'Do you get your energy from being around other people, or from being alone?
? Sensing/Intuitive'Do you see what's real, or what's possible?
? Thinking/Feeling'Do you make decisions based on logic, or feelings and values?
? Judging/Perceiving'Do you like to plan and schedule, or keep your options open?

The four scales are combined to make sixteen total personality types. Each person's Type is described using a four-letter abbreviation; ISTJ, for example, or ENFP. The most common combinations for couples are a match for 2 out of the four scales; for instance, an ESTJ might be married to an ESFP. This means that most couples have a significant common ground in the way they think and make decisions. It also means that most couples have significant differences.

To find out your personality type, and that of your partner, the most accurate way is for you both to take the official Myers-Briggs Type Indicator. This is an approximately 45-minute test that has been extensively researched and validated. Your results will tell you your four-letter type and those of your partner, and allow you to compare your similarities and differences. Recently the MBTI has become available in an online format which provides same-day results'so you and your partner can make a weekend project of studying your personality types.

Once you have figured out your Type and your partner's, you're ready to take a look at how they interact. Here's a look at how differences can play out in a relationship:

? Introverted partner with Extroverted partner: Often, an Extrovert can draw out an Introvert and introduce them to social events they wouldn't normally gravitate to. Similarly, an Introvert can help an Extrovert become more focused and self-reliant. Friction arises when an Extrovert wants more social interaction than their Introvert partner. The Extrovert may need to learn to be okay with attending gatherings alone.

? Sensing with Intuitive: As we saw in the example of David and Julie, this couple has fundamental differences in the way they think and place importance on different aspects of life. It's important to focus here on the way these two qualities complement each other in a relationship; both aspects of this scale are needed for an effective team.

? Thinking with Feeling: This is the only scale with a gender difference'which means that women are more likely to be Feeling types while men are more likely to be Thinking. Having a balance on this scale can work well if each partner remembers that the other has something important to contribute. In every decision made together, both the logic of the situation and the values and feelings of all involved should be considered. Each partner should keep in mind that no decision should be made with only the head, or only the heart.

? Judging with Perceiving: This difference most often shows itself in a simple exclamation: 'Why is he (or she) always late!'? A Judging partner will sometimes see a Perceiving partner as flighty or unreliable; while the Perceiver may get frustrated that the Judger can't seem to be spontaneous. Again, the value comes in appreciating the difference. A more spontaneous partner can help a Judger to remember that not everything has to be planned and decided in advance, and a Perceiver can use a reminder that sometimes things do just go more smoothly when there is a plan or schedule.

If you're coupled with someone who has a different personality type than you do, remember, most successful couples do have significant differences. In fact, ten percent of couples have none of the scales in common. The key lies in understanding your differences, and remembering that your partner's different viewpoint is an important contribution to your success as a couple.