An invitation arrived in the interoffice mail the other day, requesting my presence at a reception honoring the people who had worked at The Washington Post for the past 20 years.

My first reaction was to throw the invitation away before I was contaminated by association with something so pathetic as joining a bunch of geezers whose reward for being chained to the same desk for 20 years was a free buffet. Whaddya get for 25, a pass to the dog track?

But I opened the envelope, and as I read through the list of the people being inducted in the Twenty-Year Club, I noticed a familiar, but jarring name.

Anthony I. Kornheiser.

Gaaack!

(I suppose it's possible someone could genuinely feel that it's a wonderful accomplishment to work at the same place for 20 years. But it doesn't make for a very good pickup line. How much action do you think you'd get in a singles bar telling some babe, "Check this out. I've worked at the same place for twenty years.")

I immediately panicked. I am totally insecure about my job. I have spoken with several people in upper management and they've said, "Oh, you have nothing to worry about. We'll never fire you, Tommy." But I feared that my entry into the Twenty-Year Club would call attention to the fact that I've been writing the same jokes for several administrations now, and even though my references to Franklin Delano Roosevelt are pithy and insightful, the audience for them is, well, rotting.

So I went directly to the editor, a fine and loyal and generous man--did I mention he was a personal hero of mine?--and I said: "I just found out I'm in the Twenty-Year Club. I guess this means I'm assured of a job here for the rest of my life, right? I mean, you're not thinking of firing me, are you? Hey, did I tell you the one about Eleanor and Fala?"

He was very reassuring. I don't remember the exact words he used, but some of them were: "Next time you want to see me, make an appointment, Timmy."

In a way, this was worse than turning 50 and getting an AARP card in the mail. Eventually, everybody turns 50. (Plus, who wouldn't welcome a 15 percent discount on Preparation H?) But there is free choice in working at the same place for 20 years. Nobody has to become part of the furniture.

I remember when I first came here. I was young. I was ambitious. I was going to turn this newspaper on its ear. I was going to fight with my bosses, and leave in a blaze of glory and do something truly meaningful--maybe open a tanning salon or become an ombudsman. I couldn't be here 20 years already. Where did the time go? What did it all mean?

My friend Tom tried to cheer me up by explaining: "It just means you weren't good enough to do anything else. All you could do was curl into a fetal position, hold on tight and wait."

I called my friend Nancy. Her name was on the Twenty-Year Club list as well.

"How do you feel about this Twenty-Year Club?" I asked.

"Excuse me," she said. "Do I know you? You must be confusing me with my mother."

"I'm thinking of writing about this. What stands out most about working here for 20 years?"

"Losing muscle tone," she said.

I had to face it: All I had to show for 20 years was the same address. Why couldn't I have done something more noteworthy for 20 years--like not only founding the Hair Club for Men, but being a member, too?

I carried the invitation home and told my family it depressed me.

"I've been in the same place since 1979," I sighed.

My 13-year-old son showed surprising sensitivity: "You were alive in the '70s?"

As the week wore on, it became public knowledge I'd been at The Post for 20 years. Co-workers who congratulated me on being here so long fell into two categories: The older ones were delighted I'd crossed over to their side, and very soon would be crossing over to the other side. The younger ones were probing for weakness. I could read their thoughts:

"If I read one more FDR joke, I'm going to choke that old fart. I should have his job. He can't have much time left."

Every time I coughed, I gave them hope.

This Twenty-Year thing has the stink of death about it. One night you're celebrating at the Twenty-Year Club, and the next day your bosses are telling you it's time for you to "face new challenges."

Every day in offices around the country, someone my age is being asked to "face new challenges." The next thing you know, you're standing in front of his desk eating a piece of goodbye cake, and he's flying out the door like a pinata.

I used to pride myself on being a Young Turk, an insurrectionist. Now I'm a pensioner trying to hang on until retirement age, softly padding the hallways, drinking soup out of a thermos. The key, of course, is to suck up to all the bosses. (What an insurrectionist I've turned out to be, huh? That reminds me of a great Eugene V. Debs and Cordell Hull joke. You got time for it?)

The good news is that several of my bosses have been here even longer than I have. The bad news is that one of them hasn't. He barely shaves. I once asked him about Paul McCartney, and he said, "The guy in Wings?" He's the one I'm most afraid of.

Lately, Nancy and I have started smiling at him all the time. We're trying to appear young and vibrant to him. For example, Nancy has started to wear capri pants to work, and I bought one of those wigs with dreads hanging from it and a boom box. Whenever I see him, I try to mention something really obscure that happened on the latest episode of "Felicity."

They give you a pin for making the Twenty-Year Club. I'm told the pin is engraved, but the engraving is so small that nobody who's been here 20 years can read it.

A pin. What do I do with a pin? Maybe I should put it through my tongue.