It's a special event at which a wedding dress designer (or representative from the company) visits a bridal boutique on a set day with his or her entire line of new dresses. Brides schedule appointments to try on the dresses and meet with the designer.
Why have trunk shows?
Since most bridal salons often only carry a few dresses from a select group of designers, trunk shows allow customers the opportunity to see and try on dresses that they wouldn't ordinarily see at that store. If you find a dress you like during a designer trunk show, ask if the store carries it. If it doesn't, find out which stores do or get ready to buy!
Who benefits?
The bride benefits because she has the opportunity to talk to the actual designer, to discuss the gowns and any changes she may want to make to the one she's considering for herself. Designers benefit because they get to watch brides try on their gowns and listen to their comments. It's a great opportunity for them to learn directly from the consumer what they're doing right -- and wrong! The bridal salon benefits because it gets to show -- and possibly sell -- dresses that aren't part of its regular stock.