Abstract: In a method for factory planning and a model assembly (13) that is used to perform the method, the models (24, 25) of the model assembly are provided with information carriers (26) such as two-dimensional bar codes so that the position thereof can be determined by digital image processing after placement on the underlayment (14). Thus the real models (24, 25) can be used for concrete factory planning by a three-dimensional, real model, wherein it is possible to transfer the data arising in such a way into a planning program by the information carriers. Advantageously, the method of intuitive factory planning by real models and the method of factory planning by planning programs can be combined with each other in this way, wherein an efficient interface between both planning steps is created by the information carriers, wherein the interface enables in particular also interactive work with both planning methods.