Abstract: A jigsaw comprises a plurality of pieces which can be assembled to form a picture, design, shape or some other representation, some pieces being reversible so as to at least partially alter the character of the representation. Opposite faces of some pieces may bear a different picture, color, design, symbol or other marking so that reversing them alters the visual effect of the representation, or some pieces may be non-symmetric such that reversing them actually alters the shape of the representation.