PublicWeb services are not designed to be used with specific other Web services in a composite Web service. This leads to the following requirements for the proper control of a composite Web service; 1) adaptation to changes in Web services, 2) coordinating the contexts of internal processing, 3) flexible execution of human tasks. These controls must be applied following the policies of stakeholders, such as service providers. Some previous works proposed a method that adds processes to a composite Web service. Unfortunately, they fail to implement the controls needed and do not consider the policies of stakeholders. In this paper, we propose a meta-level architecture named Service Supervision, which controls a composite Web service based on the policies of stakeholders in order to achieve the requirements. To show the effectiveness of our architecture, we mention applications that currently apply Service Supervision to composite Web services consisting of machine translator Web services and human tasks.