It's our guess that people are just born with a bit of the voyeur in them. Some weird human trait that makes eavesdropping on the conversation at the next table more titillating than participating in the one at our own. Of course, we're not the only ones who've noticed this. That's why the most popular format for radio advertising is the dialogue.

A dynamic conversation in which listeners participate as eavesdroppers provides a great opportunity to integrate an advertising message into the drama of life. But it's tough to do well. In just 30 or 60 seconds, you've got to establish characters, develop a storyline, introduce an advertising message, move and resolve the situation and call the listener to action -- all without pictures.

We find our scripts are more engaging and effective when we follow The Five Rules. When we use 'em, the dialogue sings. When we don't, it squeals.

1. Have a subtext

When you hear a radio spot that reeks of contrivance and sounds like two people ganging up on a print ad, it's usually because the writer went light on the subtext. With just a bunch of sell copy divided between tag-team announcers, it's only a dialogue in the most technical sense. But when there's no plot or personality or reason to follow the conversation, it really isn't a conversation.

Subtext implies that each voice has a life outside the dialogue. It's where their motivations and character are revealed independent of the sales copy. With subtext, we can relate to the characters and see a reason for this conversation to be taking place. And the listener can identify and connect with the advertiser on a basic human level. In a nutshell, subtext is what makes a story different from a message.

2. Break it up

One of the most common mistakes people make when writing radio dialog is to write long copy blocks. First one person says a whole bunch of stuff, then the other person says a whole bunch of stuff. That's not a dialogue. That's dueling monologues. Effective dialogues require short lines with lots of back and forth. Since you have no visuals, the back-and-forth dynamic in a radio dialogue supplies the conversation with its action. When one person drones on, the action dies. If there's a reason to have multiple voices in your commercial, don't let one of them disappear or become superfluous.

3. Keep your characters in character

Once you've got sufficient subtext and you've established credible characters, make sure they stay in character and don't suddenly turn into shills. As long as your characters operate in an environment that gives them a legitimate reason to talk about the advertiser, they (and your commercial) maintain their credibility. Some writers fear they can't inform and motivate if the characters aren't selling anything. Characters do sell, but they sell from their natural reaction to the circumstances we create for them, not as pitchmen.

4. Show, don't tell

There's an old story of a door-to-door vacuum cleaner salesman who surprised housewives by throwing dirt on their carpets. But before they could kill him, he'd quickly plug in his Hoover and suck it up. Like any good salesman, he knew that a demonstration is better than a speech. If you've got a dialogue where your characters are suddenly explaining the main point of the spot instead of acting it out, you're probably dealing with a mess, too. Create action, don't describe it. Give the listeners something to picture and react to in the present tense.

5. Go all the way

Sometimes a writer falls in love with a dialogue idea, but can't carry it all the way through. So the listener is treated to a few seconds of engaging conversation, only to be blind-sided by the early and interminably long presence of an announcer who has to explain what the dialogue was supposed to illustrate. When characters are too quickly ushered out by an announcer, it creates a sense of premature evacuation -- so to speak. Which is very unsatisfying to the listener. If your idea can't adequately integrate the information through the dialogue, abandon it or be willing to change it enough to make it work.

To see how a script that follows these five rules compares to one that doesn't, check out the two versions below.

WOMAN: Where should we eat tonight?

MAN: How about Dee's?

WOMAN: Dee's Family Restaurant? That's a great idea. We always seem to enjoy Dee's because the food is so tasty and the prices are hard to beat.

MAN: Yes, that's right. And I heard that right now Dee's is featuring their delicious halibut steak. It comes perfectly broiled with steamed vegetables and your choice of baked potato or rice pilaf. But that's not all. You can also choose the soup of the day or salad. All at a special low price. I especially like Dee's halibut with their tangy tartar sauce. And unless I'm mistaken, so does someone else I know.

WOMAN: That someone else wouldn't happen to be me, would it?

BOTH: LAUGH AND FADE UNDER ANNOUNCER

SFX: INTERIOR, BUSY AIRPORT, FOOTSTEPS PASSING BY

WOMAN: Harry?

MAN: Yeah?

WOMAN: Harry Shupeman?

MAN: Yes . . .

WOMAN: Harry, don't you remember me?

MAN: Should I?

WOMAN: Well, we only went together all through college . . .

MAN: We did?

WOMAN: And after graduation we took that trip to Greece?

MAN: Huh?

WOMAN: And we took the wrong boat and got thrown in a Turkish prison?

MAN: No kidding . . .

WOMAN: And after we escaped we got married on a sky tram in the Swiss Alps . . .

MAN: Wow.

WOMAN: Aw, but back home we thought better of it and decided to get a divorce.

MAN: Oh, no . . .

WOMAN: Yeah, we worked out the settlement over dinner at Dee's. Don't you re -MAN: -- Wait a minute! Dee's?

WOMAN: Yeah.

MAN: Dee's! Yes, I remember!

WOMAN: Well, it's about time!

MAN: The halibut steak!

WOMAN: What?

MAN: We had the halibut steak. Oh, it was perfectly broiled and complemented with steamed vegetables . . .

WOMAN: Harry . . .

MAN: You had the soup, I had the salad, you had the baked potato and I had the rice pilaf . . .

WOMAN: Harry . . .

MAN: I can almost taste that tangy tartar sauce now!

WOMAN: Harry, eight years with me are a blank but you remember the tartar sauce at Dee's?

MAN: Well, mostly I remember that halibut.

WOMAN [GOING AWAY]: Goodbye, Harry.

MAN: Bye. Um, I didn't catch your name . . .

WOMAN: Forget it!

So next time you're lucky enough to draw a radio assignment, try following the above rules. We know it's not cool to follow rules if you're a creative type. Rebelling against conventions is part of your nature. But we learned a long time ago that if you ride the Horse of Creativity without the Bridle of Structure, you'll find yourself leaping into the Chasm of Confusion. This will quickly lead you to the Desert of No Paycheck.

Houston-based Radio Works founders Bill West and Jim Conlan are the authors of Radio Advertising 101.5: The Step-by-Step Guide to Creating Better Radio Advertising, from which the above is excerpted and adapted. Check