Abstract: A method for preparing and assembling a planar reinforcement for a concrete element according to a pre-determined design plan, wherein a full-sized plan including the position and type of each element in the reinforcent to be achieved is mapped onto a working surface (30) having two reference directions, a suitable reinforcement element is positioned in each of a plurality of crossing points. The method is characterised in that one or both of the mapping and assembling operations are performed by a tool attached to the carriage of a robot (10), said carriage (10) having at least two degrees of freedom parallel to the reference directions. The method further comprises storing all the design plan data in a storage area of the robot, and using the robot to move the carriage (10) automatically in accordance with said data.