An arrangement for producing a reinforcement cage characterized in that said arrangement comprising a control unit, and an assembler, the control unit being arranged to provide reinforcement cage information relating to at least one from the group of position, order, and dimension of reinforcement bars in said reinforcement cage, and the assembler being arranged to assemble, one by one, reinforcement bars in accordance with said reinforcement cage information, thus producing said reinforcement cage, the assembler comprising a reinforcement bar provider, at least one carrier robot, and an attachment robot, wherein the reinforcement bar provider is placed next to a first side of a surface, said first side extending in a first direction, wherein the at least one carrier robot and the attachment robot are movable above the surface in the first direction and a second direction, wherein the second direction is orthogonal to the first direction, such that the at least one carrier robot and the attachment robot can be moved over the entire part of the surface, the at least one carrier robot being arranged to pick, one by one, reinforcement bars from the reinforcement bar provider and to arrange, one by one, the reinforcement bars on the surface in accordance with said reinforcement cage information, and the attachment robot being arranged to attach the reinforcement bars arranged on the surface to each other in accordance with said reinforcement cage information, the control unit being arranged to instruct the reinforcement bar provider to provide reinforcement bars in accordance with said reinforcement cage information, the reinforcement bar provider further comprising a supply having a plurality of rolls of reinforcement bar, the reinforcement bar provider being arranged to select a roll of reinforcement bar having a dimension in accordance with said reinforcement cage information, retrieve a part of the roll of reinforcement bar, wherein the part being a single-bar element, and bend, straighten, and/or cut the part in accordance with said reinforcement cage information, the attachment robot being arranged to attach the part to other parts to form the reinforcement cage, such that solely single-bar elements are used by the arrangement for producing the reinforcement cage. a control unit, and an assembler, the control unit being arranged to provide reinforcement cage information relating to at least one from the group of position, order, and dimension of reinforcement bars in said reinforcement cage, and the assembler being arranged to assemble, one by one, reinforcement bars in accordance with said reinforcement cage information, thus producing said reinforcement cage, the assembler comprising a reinforcement bar provider, at least one carrier robot, and an attachment robot, wherein the reinforcement bar provider is placed next to a first side of a surface, said first side extending in a first direction, wherein the at least one carrier robot and the attachment robot are movable above the surface in the first direction and a second direction, wherein the second direction is orthogonal to the first direction, such that the at least one carrier robot and the attachment robot can be moved over the entire part of the surface, the at least one carrier robot being arranged to pick, one by one, reinforcement bars from the reinforcement bar provider and to arrange, one by one, the reinforcement bars on the surface in accordance with said reinforcement cage information, and the attachment robot being arranged to attach the reinforcement bars arranged on the surface to each other in accordance with said reinforcement cage information, the control unit being arranged to instruct the reinforcement bar provider to provide reinforcement bars in accordance with said reinforcement cage information, the reinforcement bar provider further comprising a supply having a plurality of rolls of reinforcement bar, the reinforcement bar provider being arranged to select a roll of reinforcement bar having a dimension in accordance with said reinforcement cage information, retrieve a part of the roll of reinforcement bar, wherein the part being a single-bar element, and bend, straighten, and/or cut the part in accordance with said reinforcement cage information, the attachment robot being arranged to attach the part to other parts to form the reinforcement cage, such that solely single-bar elements are used by the arrangement for producing the reinforcement cage.