The advent of 401(k) savings plans in the early 1980s introduced average American workers to a world of responsibility and choice in retirement planning.

	401(k) tips Financial planners offer the following tips for making the most of a 401(k) retirement account: Sock some of your paycheck into your 401(k), even if it's just a tiny fraction to start. Retirement savings take time to build and, especially when an employer offers a matching contribution, failing to deduct part of the paycheck for a 401(k) leaves a big benefit on the table, along with tax savings. Choose 401(k) investments according to your age and other factors that determine the degree of risk you can accept. As a rule of thumb, professional money managers recommend that investors calculate the percentage of stocks or stock funds they should hold in their accounts by subtracting their ages from 100, or 110. According to the rule, a 25-year old would have 75 to 85 percent of his or her investments in stocks. Review the mix of assets in your account periodically, perhaps as often as quarterly, but at least once a year. Rebalance the assets if they are too far out of line with your original targets. Market fluctuations can shift your account too far toward stocks or bonds even when your mix of contributions hasn't changed. For example, if the value of your stock funds increase by 20 percent one year and bond funds remain level, stocks take on a greater share of your overall holdings than planned. When rebalancing assets, do it in the context of your entire retirement savings, not just the slice of the pie in your 401(k). It's your entire nest egg, including investments in IRAs and in a spouse's retirement accounts, that should pass the "asset allocation" test. If your plan administrator offers any "automatic" options that a growing number of employers are introducing to their 401(k)s, take them, unless you really want to manage the account yourself and have the expertise or plan to seek it. If you are changing jobs, roll your 401(k) into another retirement account rather than cashing out, even if you are young, a new car seems tempting and the amount you have accumulated is small.

Now more than two decades later, it appears that many either don't want to take their retirement accounts into their own hands or aren't very good at managing them when they do.

Investment industry surveys and other studies show that more than a quarter of those offered 401(k)s by their employers don't contribute to them. Moreover, many of those who do participate make few of the choices or changes in their accounts that professional money managers would advise. At a time when the Bush administration wants similar private accounts to supplant part of Social Security, investment industry research shows that for reasons ranging from procrastination to fear of the unfamiliar, many Americans fail to manage their retirement accounts well, if they manage them at all.

As a nation of 401(k) managers, "we make mistakes every step along the way," said Alicia Munnell, director of the Center for Retirement Research at Boston College and author of "Coming Up Short: The Challenge of 401(k) Plans."

Most experts said the biggest mistake workers make is not participating at all in 401(k) plans, particularly when employers offer matching contributions, as most do.

"It means [employees] are leaving money on the table," Munnell said.

But there are plenty of other missteps. "Of those who do [participate], over half don't diversify, meaning they invest either all in stocks or all in bonds," Munnell said. Given the option, employees also heavily invest their 401(k) contributions in their own companies' stock, a practice whose dangers were underscored in corporate flame-outs such as Enron's.

In addition, those who invest in 401(k)s seldom rebalance their portfolios to account for changes in the market or to reduce risk as they grow older. During the bull market of the late 1990s, Munnell said 401(k) participants, on average, saw their accounts only slightly underperform traditional pension funds run by professionals. But that was because they were overloaded with stocks. Data since then suggest "they got killed when the market crashed," she said.

The final mistake, Munnell said, is more than half of 401(k) participants take money from their accounts before retirement. Most of the withdrawals come as employees, particularly younger ones with smaller balances, change jobs. But people yield to other temptations too, said Munnell, who confessed she tapped her own 401(k) to pay for her daughter's wedding.

If a retirement specialist such as Munnell deviates from investment dogma --most financial planners would advise against raiding retirement savings -- is it any wonder that most people who are less well versed in money management do?

Not really. After years of relying on education programs and tinkering with tools such as employers matching contributions to engage employees in their 401(k)s, benefits specialists have turned to behavioral researchers for more help. The relatively new research suggests human nature keeps many people from making any decisions regarding their accounts, much less the right ones.

Some of the findings are counterintuitive. While conventional wisdom suggests people want the widest possible selection of goods when they shop, "it's a proven that people are overwhelmed by choice," when it comes to investments, said Stephen Utkus, director of the Vanguard Center for Retirement Research, a unit of Vanguard Group Institutional Investors.

Utkus' research suggests that for every 10 funds that a 410K plan offers beyond the initial 10, participation drops by 2 percent.

But a good bit of what behavioral researchers have found regarding investor behavior isn't all that surprising.

Take failing to participate at all in a 401(k), for example. "You can come up with all kinds of sophisticated theories [of why some employees don't enroll] but when you [survey] them, it's because 'I didn't get around to it,' " Utkus said.

Given that, educating people, long the investment industry's biggest concern, isn't always the answer. Often, it's simply that employees "need to take action," Utkus said.

Debra Ceyrolles, a Neville Island resident who works as a secretary, has a 401(k) problem: For more than a year , she has received warnings in her 401(k) statement that her investment allocations were out of sync with her age.

At 51, she knows she should do something about it and eventually intends to seek help from a financial planner. But for months, she's piled the statements in a drawer.

"It scares me that I don't fully understand it, so I ignore it," Ceyrolles said.

Fear is another natural response that keeps people from making changes in the financial realm where many people lack expertise and have little time or inclination to acquire it, said Munnell, at Boston College.

"Just the effort you have to put into figuring it all out seems overwhelming," she said. "Then there's this fear where [people] just freeze and don't do it."

Wary of investments they don't understand, employees can err equally by gravitating toward the familiar. That's what drives some workers to invest too much in their own companies' stock or to put a disproportionate amount of their 401(k) savings in familiar, money-market funds or similarly low-return assets, Utkus said.

401(k) participants seem to have a healthy regard for their limitations: A Vanguard survey a few years ago showed eight out of 10 of them wanted either advice or other professional help to manage their accounts.

Employers also appear to sense problems. In a new survey from Hewitt Associates, an employee benefits consulting firm, only 12 percent of large employers expressed a high degree of confidence that employees understood their retirement benefits, and 20 percent expressed little or no confidence. Only 18 percent expressed a high degree of confidence that their employees would retire with sufficient assets, and 19 percent expressed little or no confidence that they would.

The upshot: More employers are considering automated features for their plans, including automatic enrollment and automatic management of certain maintenance functions, such as rebalancing investments, said Lori Lucas, Hewitt's director of participant research.

In the meantime, "Plan sponsors continue to communicate heavily to workers," she said.

The reasons employees' actions don't necessarily match up with the information is very simple, Lucas concluded. "Either they don't feel up to the challenge, they don't have time or it's just not getting on their 'do' lists."