Most bridal boutiques carry only a select number of gowns from a designer's total collection.  For a trunk show, the designer will send a "trunk" full of additional gowns to the boutique for a limited amount of time.  During a Trunk Show brides get the benefit of viewing a much wider selection of a designer's collection than would normally be carried at the boutique.  In addition, gowns purchased from that designer's collection during the trunk show receive a 10% discount.