One moment, the summer of your work life appears endless and so do your opportunities.

The next, you start to notice small signs that it is winding down--and faster than you thought possible.

Colleagues you once lunched with begin retiring. But, hey, they're older than you.

You mention a famous account or case that you worked on and draw blank stares.

You hear a co-worker described as "too old" for a job, and he's 15 years younger than you are!

And even more ominously, you begin to wonder about whether you have enough money in your pension, Social Security, 401(k), IRA and savings.

Suddenly it occurs to you there are worse possibilities out there than having your musical tastes and fashion sense consigned to the junk heap of fogydom.

That's when most of us suddenly begin to think about financial planning for retirement.

It's going to be a hot topic. Right now about 12.7 percent of the population, about one of every eight Americans, is retirement age--65 or older. In 2030, when two decades' worth of baby boomers have crossed that threshold, the percentage will be about 20 percent, or one out of five.

This wave of retirees will be different from the retirees that preceded them. They will live longer. They may work longer. They are less likely to have an employer-funded pension benefit built up through a lifetime of working for the same company. They will become eligible for Social Security benefits at a time when the fund may run out of money.

Many workers in their 40s and 50s have accumulated some retirement savings--almost by accident. When Congress authorized tax-advantaged individual retirement accounts, they set aside some money because it seemed silly not to. When their employers started 401(k) plans and offered to match savings, they figured, "Why not?"

We asked Washington area workers who are in their late 40s or early 50s to share with us details of their financial planning for retirement. Then we asked four experts who make their living thinking about retirement income and related issues to take a look and share some advice.

Hundreds of readers responded to our request for volunteers. Starting on Page H4, you can read about seven of them who filled out a lengthy questionnaire and who talked to us further about their households' finances.