Abstract: A slide puzzle having a number of flat slide-pieces which are slidably retained in a space formed in a plate by means of interengaging grooves and flanges. The upper surfaces of the plate and slide-pieces fall into the same plane and the space in the plate is dimensioned such that at least one portion of the space corresponding to one slide-piece always remains open. The space in the plate may be formed by an I-shaped opening, a circular recess with a short dead end portion linked to it or a rectangular recessed portion.