Construction Industry can and have been criticised for high waste of construction materials (plasterboards, windows, doors, toilet equipments etc, even organised thefts must be suspected); low quality (e.g. mould in new houses); very conservative management and also conservative trade unions. All this ending up and creating low efficiency. Investigations show that the Construction Industry has a lower productivity and efficiency than the ordinary manufacturing industry. We show a short overview of the administrative systems used in Construction Industry (in the Nordic countries). Traditional ERP-systems (like SAP/R3, Oracle etc) are not used in the construction processes. Planning and scheduling of a construction project is to a high extent still done without help from a computer system (compared to ordinary manufacturing companies). We present and discuss arguments why traditional ERP-systems not are used; e.g. a traditional work centre does not exist in a Construction project!? We then argue how a construction project should be notified, in what stages; and what in what stages of the project. Such that plans for purchase, supply and other necessary resources can be created; such that the "critical line" continuously can be followed, studied and overruns avoided. Necessary ingredients are prescriptions (e.g. how a wall is built from plasterboards, which is not the same but something similar to ‘routings' in traditional manufacturing); tasks (e.g. building an inner wall at a special work location); resources (people and machines with special skills that perform the different tasks); items (construction materials, a task to be performed requires resources, items and tools). For the tasks immediate predecessors must be determined. 3D-presentations are necessary and the work locations, place, are much more important and necessary than in a traditional ERP-system. Subcontractors are much more common also compared to traditional ERP-systems and a resource that must be well considered in the planning and scheduling of the construction project.