Abstract: A two-piece collapsible, pop-up display having an outer shell fabricated from a single piece of sheet material having an inside surface and an outside surface, and an insert fabricated from a single piece of sheet material, wherein the insert is attached to the inside surface of the outer shell. The outer shell and the insert having cooperating/corresponding pre-perforated apertures and shelf panels, respectively. The outer shell and attached insert are movable between a first, flat position and a second, deployed position in which the outer shell and insert cooperate to define one or more shelves for displaying product for sale.