(8)A contract should be deemed to be a public works contract only if its subject-matter specifically covers the execution of activities listed in Annex II, even if the contract covers the provision of other services necessary for the execution of such activities. Public service contracts, in particular in the sphere of property management services, may, in certain circumstances, include works. However, in so far as such works are incidental to the principal subject-matter of the contract, and are a possible consequence thereof or a complement thereto, the fact that such works are included in the contract does not justify the qualification of the public service contract as a public works contract. However, in view of the diversity of public works contracts, contracting authorities should be able to make provision for contracts for the design and execution of work to be awarded either separately or jointly. This Directive is not intended to prescribe either joint or separate contract awards.