A bookend system that has first and second relatively moveable members. Each moveable member has a substantially planar vertical surface for engaging objects to be held therebetween and a horizontal leg. The horizontal leg of the first member has a central open are with opposed parallel interior edges which receives the horizontal leg of the second member, which has interfitting opposed parallel edges. The adjacent edges of the first member and the second member are connected by at least one joiner that slidably captures the parallel edges. The joiner may take the configuration of an I-beam, having upper and lower flanges joined together by a central web. In such an embodiment, the opposed parallel edges of the first and second members are captured in a slot formed between the flanges of the joiner.