Margot Bai is a licenced insurance representative, but as she watched the married couple argue in their home, she felt more like a divorce attorney. The unhappy pair had failed to discuss or agree on how they wanted to live together as a couple, and the financial fallout was threatening their marriage.

“I work hard, it’s my money, and I deserve to spend my money how I want,” the wife seethed.

“I work just as hard,” the husband retorted, “but I don’t have any debt – you have a pile of debt.”

Often, one person in any couple is the spender and the other is the saver, notes Bai, author of Spend Smarter, Save Bigger (available at http://www.spendsmarter.ca). Conflicts are bound to happen, she says, unless the couple takes time to talk about money before they get married. “When couples are dating their money is separate. But to form a lifelong partnership, they need to put their money together. They should have conversations about money once they know they’re committed to a long-term relationship.”

Years of resentment at each other’s spending habits had driven a wedge between the couple. And they’re not alone: studies show that a primary cause of friction in marriage is disagreements over how money is spent. How do some couples take major financial decisions in their stride, while others stumble over the smallest household expenses? Common goals provide a pattern for how you, as partners, want to live your lives together.

Here are some tips to help formulate and enact a shared money plan.

Think Big and in Buckets
Couples who don’t get mired in debating daily small expenses are usually more successful at managing their money overall, according to research by Mary Claire Allvine, a U.S. financial planner and co-author of The 7 Most Important Money Decisions You’ll Ever Make. “It’s not the daily latte that puts people in debt,” Allvine says. It’s the lavish home or upgrading to a new vehicle every few years.

Allvine recommends naming your dreams and putting the money you save towards each one in a separate fund, or bucket. “When you have a place to put the money you save by not playing golf today, or not buying that blouse, you can see it grow,” says Allvine. Watching the bucket fill gives couples incentive to persevere.

Get Tough Early
Young marrieds can live happily on a shoestring – and they should, counsels Bai. “Make any and every sacrifice you can tolerate in those early years. By the time you reach your 30s, your savings will have a huge impact for the rest of your life.”

By foregoing designer dresses, a big-screen TV or long holidays, young couples will accrue cash for a home, a car, and investments. Saving on those big-ticket items, she says, makes more financial sense than coupon clipping or buying in bulk. She recommends getting a sensible car and hanging onto it as long as possible, buying a house that will appreciate in value, and being wary of financial advisors steering clients to mutual funds with high fees.

Put it in Writing
Couples who agree on spending have agreed on their fears and goals, says U.S. syndicated radio talk-show host Dave Ramsey. Money is directly tied to people’s deepest needs and fears: it can be a security blanket, or sense of failure. When a couple puts their financial plan on paper, it strengthens their promises, cooperation and sense of unity.

Ramsey recommends regular meetings to review expenses, where nothing is hidden. There are no secret debts or credit cards. The couple discusses what to spend on Christmas presents, how to finance a child’s braces, and what to budget for a new suit. It makes life real, says Ramsey.

Walk the Dog
Choose the right time and place for money talks, advises Carrie Schwab-Pomerantz, chief strategist with financial services provider Charles Schwab & Co., Inc. of San Francisco, and co-author of It Pays to Talk. Don’t wait until the end of the day, when you’re both tired, or face off on opposite sides of the kitchen table. And don’t suddenly spring the subject on your mate.

“When I was pregnant with my oldest child, my husband Gary and I would walk through a park by our home in Atlanta every Sunday morning, throw the ball for our dog, and discuss our future,” Schwab-Pomerantz recounts. The relaxed atmosphere and neutral territory allowed them to discuss their dreams and tackle difficult topics like their finances while keeping the peace.

The Dreaded Prenup Talk
Instead of getting easier with age, it’s even more difficult for older couples to discuss money, says Allvine. Yet merging finances is just as important when you marry later in life, or enter a second marriage. The aging parents who need care, the irresponsible sister-in-law, the children from another marriage: these are all excuses older couples use to keep their money separate. “It’s one of the biggest errors they make,” she says. “When a crisis arises, whose money is it?”

A prenup agreement can be as simple as stating “what’s mine is yours, and what’s yours in mine,” Allvine notes. At the very least, a prenup conversation that reveals the values of each partner is necessary.

Togetherness pays
If you live together as a committed couple, you should have a single chequing account – a joint account, advises Bai. A joint account is a clear statement that “you want to work together towards common goals,” she says. “That way, you’re both responsible. You both have to keep to the budget you’ve made together.” Joint accounts also send a strong signal to each other that your marriage comes first.

Managing your money can seem as romantic as a bouquet of cold fish, but being on the same wavelength removes friction that can curdle love. “Put the romance back in money,” Allvine. “Money is only as good as what you want to do with it, and what you’ll do with it is realize your dreams.”