Request: Your third cousin asks to bring her boyfriend-of-the-month to your $150-a-plate wedding reception.

What you should say: "We've already had to make so many tough decisions to get the guest list down to size. We really can't squeeze in/afford another guest. But I would love to have you two over for drinks sometime so I can meet him."

Why it works: If you illuminate some of your behind-the-scenes planning, your cousin may get a clue about the inappropriateness of the request.

Why you shouldn't feel guilty: It's your party and your pocketbook, says author Patti Breitman.

How to avoid the situation in the future: Make a few calls before you put together the guest list to see if there are new additions you should consider as you plan.