(43)For works contracts, such situations include works that are not standard buildings or where works includes design or innovative solutions. For services or supplies that require adaptation or design efforts, the use of a competitive procedure with negotiation or competitive dialogue is likely to be of value. Such adaptation or design efforts are particularly necessary in the case of complex purchases such as sophisticated products, intellectual services, for example some consultancy services, architectural services or engineering services, or major information and communications technology (ICT) projects. In those cases, negotiations may be necessary to guarantee that the supply or service in question corresponds to the needs of the contracting authority. In respect of off-the-shelf services or supplies that can be provided by many different operators on the market, the competitive procedure with negotiation and competitive dialogue should not be used.