Mandate. Latin mandatum, task, job, order to do something for another; to represent another legally; an elected office to represent the voters.
A mandate is a broadly defined task where the service provider – consultant, attorney, architect, subject area expert – advises the client. The business relationship is not made up of small, individual tasks.
Instead, the service provider – the person who has been granted the mandate – serves, represents, and advises the client in a complex area involving many different kinds of issues and interactions.
Attorneys represent their clients in legal matters. Political office holders represent their voters. A mandate obligates the adviser to act in the interest of the client even without the client‘s expressed permission.