Fuente: WIPO "rice" A foldable viewer includes a front wall having a pair of lens-receiving openings and a pair of optical lenses affixed thereto. A rear wall is included and has a pair of openings over which transparencies depicting stereoscopic images are affixed. The front and rear walls are attached to top, bottom and side walls to create a box-like structure when assembled. The walls cooperate to form a bellows-like structure that permits the viewer to be flattened for storage, mailing or placement in a magazine-like publication.