Come retirement, you may want to clean out your desk, shake hands with the boss and walk out of the place forever.

But don't, suggests Steve Goldberg, executive director of the National Association for Retired Credit Union People, slam every door behind you.

Even as an ex-employe, he says, you can almost always retain your membership in your company credit union. About 85 percent of the nation's 22,000 credit unions welcome retired workers.

It is not something to give up hastily, says Goldberg, if over a period of 20 years or so you have sought financial help and built up a credit rating.

"Retirement is a time of stress and uncertainty. You don't want to lose touch with the institution when you may need it the most. You need all of the help you can get." For example, Social Security or other retirement income may be deposited directly to avoid loss in the mail.

Of course, the credit union needs you, too. Says Goldberg: "The only way younger members can get low-cost loans is if older members put money in the credit union."

His association's aim -- as an affiliate of the Credit Union National Association -- is to promote continued post-retirement use of credit unions. For a $10 annual fee, it also offers retirement services and advice.

Among them: Two quarterly magazines and a quarterly newsletter (12 mailings) with financial, medical and other reports geared to retirees; supplemental insurance policies; reduced-cost ("15-30 percent") pharmacy service by mail; an emergency cash service; and help with consumer complaints.

Recently, says Goldberg, the association came to the aid of a Texas couple who had put a $3,000 deposit on a new car with a dealer across the state line in Louisiana. The dealer went out of business, and a year later the couple still had neither money nor car.

"We wrote to Detroit to express the concern of our members and to the attorney generals of both states. Two weeks later we got the deposit back from the parent auto company. We have a little more punch than an individual consumer."

Established in 1978, the association now has 28,000 members and is growing, says Goldberg, at the rate of about 1,000 to 2,000 a month. Membership is open to retired individuals who are or were credit union members or still-employed members who are at least 50, and spouses in both cases.

For more information: Contact your credit union, or write National Association for Retired Credit Union People, P.O. Box 391, Madison, Wis. 53701. Phone: 608-238-4286.