1. "How do you keep the friends occupied?"

Specifically, ask about contests and games. Hope for more than "Coke & Pepsi" and "The Limbo." Kids must be kept happy or, at the very least, busy. But a DJ isn't a baby-sitter. He can't be in the hallway preventing them from playing "Keep Away" with a bagel!

Most kids wear their halos. Occasionally they're rambunctious. They're 13. The maturity level of some is, well...let's say...yet to reach it's peak. (Not your child's, naturally.) Devilish plans can be concocted in the rest rooms, so don't even invite any rascals. Your child knows who they are. GOOD: Your cup runneth over with love. BAD: The toilets runneth over with paper towels.

At this age, no children are accomplished dancers. But for me, Bat Mitzvahs are easier than Bar Mitzvahs.

Daughters will invite more girls. Sons will invite more boys. Girls won't hesitate to jump onto the dance floor to do a line dance or cheerleader routine.

But unless it's an interactive song that doesn't require a partner (such as "The Electric Slide" or "Cha-Ca Slide"), boys will never dance with each other. They'll punch each other. They'll commiserate with each other. They'll chase each other. They'll pound each other over the head with inflatable guitars. (This is all fun for them, by the way.) But they'll never dance with each other, so I run more games.

I'm not there to scold. If you can, try for a nice boy/girl mix.

The Baltimore Jewish community is provincial, with its population concentrated in four adjacent zip codes. I see many of the same children at different parties. There's always a fresh, awkward group in January. By Spring, they've been to several parties and are more gregarious. By Autumn, I'd better come up with new approaches and fresh jokes because many of these kids have caught my act already. They request slow dances and are becoming socially adept. Hey, that's progress! (And I look forward to January again.)

2. "Can you play all eras of music?"

End of conversation if the answer isn't "YES!"

I go to jobs ridiculously overloaded with 7,000+ tunes. I'll play 70. This has been my occupation for a long time. I know what people are going to request and I have their favorite tunes with me.

When I MC, dancing is not a spectator sport. Just give a competent DJ your guests...he'll give you a party!

A Mobile DJ will arrive with Greatest Hits compilations and anthologies including Jitterbugs, British, Motown, Disco, etc. He may have sound effects known as "drops" to use sporadically.

I keep up-to-date musically with a CD subscription to "Promo Only." It's one of several available DJ services issued monthly that anticipate the hits. Each CD issue contains 18-20 tracks by various artists. This allows Mobile DJs to obtain the individual tunes which national Radio Program Directors feel will be "hot" each month, without having to purchase 18-20 individual CDs.

At seminars, we've actually laughed out loud at certain DJ promotions brought to our attention, such as: "Select From Our Music Library Of Over 100,000 Songs!" WOW! Break out the confetti! (...Hold on a second. Let's think this through. You guys wouldn't be fibbing would you? Are you sure it's not 99,827?) Besides, 100,000 songs would require schlepping 5,000 CDs. That load would weigh a half a ton. Literally! Who are they kidding? And if it were true, what kind of CD titles are they bringing? "The Mormon Tabernacle Choir Hums Mozart?"

3. "What brand of mixer do you use?"

I'd bet this question would surprise the DJ. I know I've never heard it! Many clients don't know what a mixer is! (Nor care.) It doesn't matter. Ask the question. Unless you're familiar with audio gear, you won't recognize the difference between pro and consumer brand specifications.

A Mobile DJ should have mobile grade equipment. If he mentions brands you could purchase at Sears, it's cause for concern! Even a fine home component stereo system is not designed to stand up to hours of high volume use. It could fail in the middle of your party! DJ amps may deliver 500 watts or more, where as a robust living room unit may top out at 70. It's cleaner to have powerful Mobile DJ equipment played at softer volumes than to have an inadequate system strain.

Listen for brands such as American Audio, American DJ, Denon, Gem, Gemini, MTX, Next, Numark, PioneerDJM, Rane, Roland, Stanton, Tascam or Vestax. All good. It follows that his other gear will be professional, too.

4. "Do you have a hand-held microphone?"

It's necessary for your child to be heard during the Candlelighting Ceremony or for the DJ's use on the dance floor during games. A headset or a Lavaliere (like your local TV Anchorman wears pinned to his tie) is also fine.

5. "Should I feed you?"

Unless stipulated in the contract, no. (Well...maybe just a little!) Aside from a quick munch, a DJ should be gabbing not gobbling and, with candlelighting and contests, there's way too much activity going on when the kids finish eating.

Your caterer may bill you automatically (usually at a reduced rate) for a meal for the DJ, videographer, photographer, etc. That's between you and the caterer. I certainly don't require a full meal. But it's an appreciated gesture to allow the DJ to help himself to a plate of hors d'oeuvres or a bite from the kid's buffet.

If it's not stipulated on his contract, when you arrive remember to greet your DJ and, if you wish, offer this courtesy. He's a performer. Why not put the one who will "make or break" your party in a positive frame of mind? Generally, parents are solely attentive to their own guests and never think to do it. (Please, do NOT wait until the DJ is packing up his gear to ask: "You did get something to eat, didn't you?" We grit our teeth at that one.)

What's very important is keeping your DJ lubricated, but only with coffee, soda or juice. If you open the bar to him, he might be tempted. So don't.