6.4. If this is the outcome of the market test, the parties will need to manage the process carefully to ensure that there is a seamless delivery of services. The main responsibility for managing this process lies with the PPP contractor which will also be responsible for ensuring that the new service provider fits in to any relevant interface arrangements with other service providers or the construction subcontractor (see below under Interface). However, the parties will need to inform users and contract managers of the changes and agree any transition arrangements.