A composed element, such as a piece of furniture, wherein the composed element comprises at least a rear wall, as well as a number of constructional parts forming a whole in which the rear wall has to be provided. The rear wall forms the rear side of the composed element and includes one or more rear wall parts. The composed element comprises seats for installing at least one of the rear wall parts, which are configured such that the rear wall part can be slid into the seats starting from the rear side of the composed element from a position differing from the final plane in which the rear wall part will be situated in the final condition.