Paul Schencker doesn't know where his wife's safe-deposit box is, and he doesn't know how much money is in it. Nor does he want to know.

"I believe what I don't know won't hurt me," he says.

His wife, Geri, agrees: "If he knew how much money I had hidden, he'd have a heart attack."

Geri has been squirreling money away for the length of their 10-year marriage.

The Fountain Hills,Ariz., couple is not alone. Depending on the survey, anywhere from 30 to 60 percent of spouses stash money unbeknownst to their partners. Many relationship experts frown on the practice. Financial experts think it's dangerous. But those who stash insist they possess valid, even relationship-saving, reasons.

SHE LIVES TO TRAVEL

Geri Schencker skims money from her paychecks to go on vacations. During their marriage, the couple have been to Iceland, Chile and the Amazon rain forest. The two just returned from Mexico, where they chartered a plane to the exotic island of Las Animas.

Paul has no idea how much the trip cost because his wife paid for it out of her stash.

Geri began hiding money because she likes to travel, whereas her husband preferred more materialistic ways to spend money.

"I'd rather add another flat-screen (TV) to the wall," he says.

At any given time, the safe-deposit box may hold $1,000 toward the couple's next trip. Geri says that if Paul knew the location of the box, he'd want to spend the stash on other things.

Geri reasons that the money is like an investment in the couple's relationship.

"It's really like putting the money back into our marriage because taking vacations together makes the marriage stronger," she says.

Paul says that's probably true. But Paul, who co-owns a wholesale grocery brokerage, also says his salary allows the couple a comfortable existence, so his wife's secret savings aren't a big deal.

PLENTY OF PEOPLE HOARD

Though the words "secret account" make relationship and financial experts cringe, many see value in couples knowing about, and having, separate stashes to spend as they wish.

"It's fine and can be very powerful for couples to have an account that they claim as their own," says Spencer D. Sherman, who counsels couples on money issues through his company, Abacus Wealth. "This is a no-questions-asked account so someone can buy a sweater, a (pricey) cashmere sweater and the amount can stay private."

A 2005 survey by MONEY magazine found that 71 percent of 1,001 women and men with incomes of $50,000 or more admitted keeping money secrets. The survey didn't say how many of those interviewed couples kept secret accounts, though three in 10 said they or their partner had a separate account both knew about (and in 30 percent of those cases, only the owner knew how much was in the account).

MP Dunleavey, columnist for The New York Times and MSN Money, as well as author of "Money Can Buy Happiness" (Broadway, 2007, $18.95), says she winces when couples haven't met their financial goals, including saving for retirement, paying down debt or starting a college fund.

The majority of times, Dunleavey says, money hiders simply "don't want their spouse to criticize or even remark on a purchase. It's a real privacy issue."

Money secrets become a problem when household needs are not met, such as paying the electric bill. Even under those circumstances, the desire to squirrel money away for no-questions-asked purchases is strong, Dunleavey says.

Both Sherman and Dunleavey say the need for secrecy stems from a person's beliefs about money formed in childhood.

"It all comes from the messages we picked up from our parents, television, our religious leaders," Spencer says. "Maybe that money is hard to make. Or that it's evil."

Whatever the reason, secret accounts are not uncommon, Phoenix-area radio talk-show host Darrell Ankarlo learned.

The call-in lines lit up this summer after Ankarlo revealed his own secret account, doing so only after his wife, Laurie, had stumbled upon bank statements in the midst of a family move.

It was not the account or the money that upset her, Laurie told listeners; she said she was upset by the secret.

Ankarlo took the heat, explaining that the money came from appearance fees and little deposits here and there. It financed unexpected needs of their four children, as well as gifts for her. For example, he spent some of his stash to upgrade his wife's wedding ring.

"Guaranteed, I'm not the only guy out there that does that (keeping a secret account)," he says.

NO LAUGHING MATTER

Men and women callers shared that they, too, had stashes, and most called it their fun money. Only one or two callers said their spouse's secret account funded a breakup or divorce.

Ankarlo's not-so-secret account is attached to the couple's other accounts, Ankarlo says, so if he were to die, the money would go to his wife. He declined to say exactly how much is in it but says he contributes $100 here and there - not a substantial amount, but it does provide some security.

Ankarlo says the fact that he grew up poor might have something to do with why he hides money. His father was a minister raising six children on a $16,000-a-year salary.

"So I'm sure that part of the stash concept is to make sure that I have enough to cover an emergency if it pops up unexpectedly," he says.

Even after his secret is out, Ankarlo maintains the account. He invited his wife to view the account and its trail of withdrawals and deposits, but she declined, he says.