Couple walking with their two sons © Jack Hollingsworth, Photodisc, Getty Images

One of my clearest memories as a little girl was sitting in between my parents in the front seat of our big, red station wagon -- while listening to them argue about money.

I remember thinking, Oh, they'll figure it out. They eventually did, but the lesson that I took away from that experience was that money made my mom and dad mad.

It turns out that my parents were fairly typical. According to a nationwide survey (.pdf file) conducted by LearnVest and TD Ameritrade, couples have about five fights a year about finances -- and about 20 money conversations a year.

But what is it really like to communicate effectively about money for decades? We asked those who know best: three long-term couples who've spent years talking about -- and dealing with -- money as a team.

Cindy and Mike Harrelson -- Bozeman, Mont.

For Cindy and Mike, a married couple in their mid-50s with two kids in college, it's all about being financially responsible.

Married for 29 years, they thrive on living within their means -- without debt. They don't have a dollar of credit card debt, and they own their home outright. This clear vision, which Mike likes to call being "downwardly mobile," has allowed them to live in more posh locales like Jackson Hole early in their marriage, and Hawaii for two years when their children were young.

Cindy and Mike had hard-working, frugal parents, so they both feel strongly about never buying things simply to fill a void. And money was something that they made a point to discuss early on in their relationship -- including on their first date.

"Before we got married, we said, 'We're going to need to communicate about everything -- especially money,' " says Cindy, an academic administrator. "We're going to need to pool it, and trust each other, knowing that we are sharing everything 50/50."

"Consequently, the things that we've been able to experience as a family, because we are debt-free, have been invaluable," says Mike, an avid outdoorsman who works in public relations. "Money doesn't control us." In fact, Mike recently took a surf trip to Nicaragua, thanks in no small part to the couple's savvy approach to finances.

And while Mike is the big-picture guy who tends to keep an overall vision for the family, Cindy is more of the pragmatist-spreadsheet person. "She has a clear plan of when things are supposed to happen, which has been a relief for me because I didn't always have a knack for the right timing like she did," says Mike. "She'd say, 'I think it's time to buy a house,' and that would feel right for me, too."

Brent and Linda DeHart -- Salem, Ore.

When it comes to talking about money, Brent and Linda DeHart -- who are both in their 50s, with two college-aged sons -- say it all comes down to supporting each other.

Brent, a financial adviser, and Linda, a part-time teacher, have an entire system worked out to deal with money: Brent oversees the investment and savings accounts, while Linda manages the household budget needed for things like groceries, entertainment, clothes and sports.

When it comes to major decisions, like buying a home (which they've done twice) or selling their family-owned gas station business, they do it as a team, using Brent's financial expertise to guide them.

With their system, they're able not only to manage life's ebbs and flows, but also sudden, larger costs -- like their older son's seven-year battle with leukemia. When he was diagnosed at just 2 years old, they were fortunate enough to have comprehensive health insurance, but the years that their son was very sick took an emotional toll on the couple.

"I don't know what we would have done during our son's illness if Brent hadn't taken the reins with our finances during that health care crisis," Linda explains. "Our son made it, but while it was happening, caring for him was a 24/7 job -- and I just didn't have the brainpower to make other decisions, like whether or not we needed to take a loan out to buy a new hot water heater."

"Playing to our financial strengths has given our marriage an unshakable foundation," adds Linda. "And that may be our greatest asset!"

Jim and Judy Farber -- Omaha, Neb.

According to Jim and Judy, a couple in their 70s with two grown daughters, the secret to talking about money over the course of their 37-year marriage has been cooperation and collaboration.

Although they had different socio-economic upbringings -- Jim had a more affluent childhood, while Judy's father died when she was 12, leaving her mother to single-handedly raise three children -- they were always prepared for the worst, since they both grew up during the Depression.

"When we got married, the economy was like an elephant in the room," says Judy. "It was assumed that we'd be economically conservative." Both of them learned from their parents that important life events cost money: buying a home, raising children, saving and, most important, living better lives than their parents could afford.

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"It's always been pretty simple," says Jim, a financial adviser. "If we want to buy something significant, we sit down together and say, 'Can we afford this?' "

Judy, a retired figure skater and fitness instructor, agrees, adding that the key has been to look at each life event and discuss as a team what is doable. "We were always conservative with money," she says, "because we knew that we were going to buy a house and send the girls to college."

Despite childhoods that were colored by the Depression, they've also learned that it's OK to want to spend on things that they love -- like their shared passion for travel. One of their favorite getaways was a walking tour in Ireland, and Jim loves taking golf and poker trips to Florida and Las Vegas with his buddies.

"Ultimately, we enjoy striving for a better lifestyle by using a mixture of common sense and fun," says Jim. "Let's put it this way: If Judy wants to do something, and we can afford it -- like go to the U.S. Open in New York -- chances are that we'll do it. That's probably why we've been married all these years!"

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