What is a purchase/contractor agreement? When parties agree that one of them will provide a piece of land and construct or finish a building on it for a fee, there is a contract for the purchase of the land on the one hand and a contract for work on the other hand with regard to the building. The part relating to the purchase of the land is governed by the legal rules of sale. On the part that relates to contracting work (building and delivery), the rules of contracting work apply. Therefore, it does not make much difference in practice whether one speaks of two linked contracts (purchase and contracting) or of one compound contract to which the rules for purchase and the rules for contracting apply in part.

At the start of a construction project, a client will often engage an architect, engineer or consultant to help him with the design (hereafter: 'consultant'). The legal relationship between the client and his consultant is - if nothing else has been agreed - governed by the legal rules for the commission contract. These legal rules can be found in the first section of title 7.7 of the Dutch Civil Code (art. 7:400 ff. of the Civil Code). The summary statutory regulation has a general and open character and is largely of a regulatory nature. It is therefore common for parties to make further agreements.