Abstract: The invention concerns an elevator system comprising an elevator car with a working platform arranged for carrying people or materials and which by means of the interaction between a gear wheel and gear rack can be moved along an elongated generally vertical mast constructed from a number of mast sections mounted on top of each other. To facilitate the erection, tearing down and anchoring of the mast to a nearby building structure, the moving unit comprises a passenger-carrying service and assembly platform, which, via a swing arm, is flexibly supported by the elevator car to allow a swivel action in a horizontal plane (C, D) relative to the elevator car.