Abstract: A walker includes a chassis; at least one handle connected with the chassis and adapted for moving the walker by a user; and at least three roller means attached to the chassis and on which the walker is moved on a surface. The walker is adapted so that it may be converted from a roll configuration, in which a user may push the walker in order to support himself thereon, into a sit configuration, in which the user may sit down on a sitting means, wherein the sitting means comprises a front seat element and a rear seat element, which formed in the sit configuration a sitting area, and wherein the front seat element moves with respect to the rear seat element, if the sitting means is moved from the sit configuration to the roll configuration.