(MONEY Magazine) - When IBM announced that it would freeze pension benefits in 2008 for 117,500 U.S. employees, it felt like the New York Yankees declaring that players would have to buy tickets to fly on the team jet. After all, this wasn't some bankrupt steel company. This was Big Blue, a corporate icon with a tradition of paternalism--and an icon in great shape financially, by the way. Anyone who works for a company that promises a monthly check for life had to wonder: Could my pension be next?

Not to be alarmist, but hell, yes. Up till now, you felt safe as long as your company and its pension were in decent financial shape. But even strong companies are looking to switch to a 401(k), whose costs are cheaper and more predictable. And a bellwether such as IBM putting its pension on ice (and increasing its 401(k) contributions instead) makes the move socially acceptable.

Of course, if your pension is frozen, you'll collect any benefit you've earned to that point (and retirees will get their checks as usual). But the size of your payment won't grow to reflect salary increases and years on the job. All of which means, if you work for a company that offers a traditional pension, start thinking of a backup plan.

If You're Just Starting Out, don't count on a pension at all. Not just because it might be halted. Pensions build most of their value in the last five to 10 years before retirement, and the chances that you'll stay until gold-watch time are virtually nil. So try to save at least 10% of your salary in a 401(k) if your company offers one (as most companies with traditional pensions do). If it doesn't, use IRAs and regular taxable accounts.

If You've Been at Your Company for a While--say, 15 years or more--you can expect to receive your accrued benefit (what you've already earned). But don't assume you'll end up with the larger projected payment you'd receive if you (and your plan) survive until retirement. Instead, put away as much as possible in tax-advantaged retirement and other accounts so your security won't be completely devastated if your plan is frozen or you leave before you retire. (Ask your HR department for figures for your accrued and projected benefits.)

Granted, it may be difficult to stash enough to make you whole if your plan is frozen, but anything helps. And if you end up getting the big payment after all, then what the hey, go to Europe and spend it.

If You Retire with a Frozen Pension, your monthly benefits may not be much. If you like the idea of a monthly check, consider effectively creating your own pension by taking part of the money in your retirement accounts and buying an immediate annuity--in a way, buying the same thing a pension provides: certainty. Recently, investing $150,000 in an immediate annuity could buy a 65-year-old man roughly $1,000 a month in guaranteed income for life. The amount can vary by insurer, so compare rates at a site like ImmediateAnnuities.com.

Or you could do nothing and hope your employer doesn't do what IBM did. But if you're wrong, you might end up joining your pension out in the cold.